MBOSE Class 12 Question Paper 2021 for Computer Applications

Total No. of Printed Pages—12
HS/XII/A.Sc.Com/CAP/OC/21

2021

COMPUTER APPLICATIONS
( Old Course )
( Arts / Science / Commerce )
( Theory )
Full Marks : 70
Time : 3 hours

The figures in the margin indicate full marks for the questions

General Instructions :
(i) Write all the answers in the Answer Script.
(ii) Attempt Part—A (Objective Questions) serially.
(iii) Attempt all parts of a question together at one place.
(iv) Part—A (Objective Questions) is to be attempted
according to stream as mentioned.
(v) Attempt Part—B [Descriptive (Unit—I)] according to
stream as mentioned.

( PART : A—OBJECTIVE )
( Marks : 35 )
SECTION—I
( Marks : 25 )

1. Fill in the blanks from the list of words/phrases given
below : 1×10=10
( For Science stream candidates only )
(a) Each occurrence of a variable or its complement in
an expression is called _____.

/117 [ P.T.O.

( 2 )

(b) The number of rows in the truth table for a function
of 3 (three) literals will be _____.

(c) Two switches connected in parallel behaves as _____
gate.

(d) A _____ is an implicant which cannot be wholly
enclosed by a larger implicant on a K-map.

( For Arts / Commerce stream candidates only )

(a) Network.Node.Node.Node is the format of _____
network.

(b) _____ is the primary method of transferring files over
the Internet.

(c) DNS translates the domain name into _____.

(d) _____ is the central authority for assigning numbers
to Internet sites.

( For all Science / Arts / Commerce stream
candidates : C Language )

(e) #define statement calls for simplest type of ______
substitution.

(f) A do-while loop with test condition is known as
_____ loop.

(g) C language supports _____ data types such as
pointer reference types, array and struct.

(h) _____ statement results in unconditional branching.

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( 3 )

(i) The starting subscript of an array in C is _____.

(j) FILE is defined in the _____ header file.

List of words / phrases :

Internet derived variable implicit Class C
3 essential prime NIC EOF
Class A 0(zero) OR MAC literal
conio.h NULL exit-control 8 macro
IP address goto stdio.h AND continue
DNS break URL FTP exit

2. State whether the following statements are True or
False : 1×10=10

( For Science stream candidates only )

(a) Accoding to De Morgan’s theorem
( A  B )  A   B 

(b) Fundamental conditions or self-evident propositions
are called postulates.

( For Arts/Commerce stream candidates only )

(a) Telnet can be used for remote login.

(b) To specify multiple recipients of carbon copy of same
mail message, CC : field is used.

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( 4 )

( For all Science / Arts / Commerce stream
candidates : C Language )
(c) File handling functions are prototyped in conio.h.
(d) A break statement must be used following the
statements for each case in a switch statement.
(e) The conversion specification %d is used to read the
values in decimal.
(f) The program’s ability to access a variable from the
memory is called visibility.
(g) The loop-control elements in a for–loop are optional.
(h) If an array had been defined like this : int array[11];
then the word ‘array’ represents the address of the
array.
(i) A structure is a composite data type which contains
more than one member and all members can be of
different data types.
(j) All files need to be opened with ‘fopen()’ before it is
used for reading or writing in the program.

3. Choose and write the correct answer : 1×5=5

( For Science stream candidates only )
(a) In Boolean theorem, X  X Y will be equal to
(i) X   XY
(ii) X  Y
(iii) X  XY 
(iv) None of the above

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( 5 )

(b) Which statement below best describes a Karnaugh
map?

(i) The Karnaugh map eliminates the need for
using NAND and NOR gates.

(ii) A Karnaugh map can be used to replace Boolean
rules.

(iii) Variable complements can be eliminated by
using Karnaugh maps.

(iv) It is simply a rearranged truth table.

( For Arts / Commerce stream candidates only )

(a) In the term ‘IP addresses’, IP stands for

(i) International Protocol

(ii) Internet Protocol

(iii) Internet Provider

(iv) None of the above

(b) In a client/server system, a client issues request to

(i) hyperlink

(ii) mainframe

(iii) a server

(iv) a token ring card

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( 6 )

( For all Science / Arts / Commerce stream
candidates : C Language )

(c) When applied to a variable, what does the unary ‘&’
operator yield?

(i) The variable address

(ii) The variable right value

(iii) The variable binary form

(iv) The variable value

(d) Which of the following is a valid example of constant
definition?

(i) N 25;

(ii) #define X=2·5

(iii) #define PASS_MARK 50

(iv) All of the above

(e) The functions fgets() and fputs()

(i) read and write strings from or to data files

(ii) read and write strings from or to input/output
stream

(iii) read and write records from or to data files

(iv) None of the above

HS/XII/A.Sc.Com/CAP/OC/21/117 [ Contd.

( 7 )

SECTION—II
( Marks : 10 )

4. Answer any five of the following in not more than
3 to 4 sentences each : 2×5=10

( For Science stream candidates only )

(a) (i) Find dual of the following logic expression : 1
1  X .Y  Y .XZ  0
(ii) What will be other canonical form for the
following Boolean expression? 1
F (a , b, c )  (0, 2,5)

(b) Simplify the logical expressions : 1+1=2
(i) A  A B
(ii) A.(A   B )

( For Arts / Commerce stream candidates only )
(a) What is a URL? Does it case-sensitive? 1+1=2

(b) What is the purpose of the reports view in
FrontPage?

( For all Science / Arts / Commerce stream
candidates : C Language )
(c) Describe two different ways that floating point
constants can be written.

(d) What is the purpose of the if-else statement?

(e) In what two ways can a structure variable be
declared?

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( 8 )

(f) State the rules for naming an identifier.

(g) What is the difference between fprintf ( ) and
fwrite( ) functions?

( PART : B—DESCRIPTIVE )
( Marks : 35 )
UNIT—I

( For Science stream candidates only )

5. (a) Explain minterms and maxterms. 2

(b) State and verify absorption law using truth table.
1+2=3
OR

6. (a) Verify the following using Boolean laws : 2
A  C  A  A  C  B  C

(b) Name the Boolean law shown below and verify it
using a truth table : 1+2=3
A  B  C  (A  B )  (A  C )

7. (a) Using Karnaugh map method, simplify the following
function : 2
Y  A B C   A BC   AB C

(b) Realize the logic expression AB  BC  CD using
basic gates. 2

(c) Define constant signal. 1

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( 9 )

OR

8. (a) If
F (a , b, c , d )  (0, 1, 3, 4, 5, 7, 8, 9, 11, 12, 13, 15)
obtain the simplified form using K-map. 3

(b) What is meant by ‘don’t care’ condition? Explain
with the help of a K-map. 2

( For Arts / Commerce stream candidates only )

5. (a) Distinguish between a Web browser and a Web
server. 2

(b) What is domain name? What is the role of DNS on
the Internet? 1+2=3
OR

6. (a) What do you mean by cross-platform? 2

(b) What is a mail header ? What does it contain? 1+2=3

7. (a) How to add check boxes on a Web page design
through FrontPage? 2

(b) What do you mean by slow pages? How to check for
slow pages? 1+2=3
OR
8. (a) How to add a ‘theme’ to your Web site using
FrontPage? 2

(b) Describe various steps for inserting a hyperlink in
FrontPage. 3

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( 10 )

( Unit-II, Unit-III and Unit-IV )
For all Science / Arts / Commerce stream
candidates : C Language )

UNIT—II
9. (a) How can comments be included within a
C program? Where can comments are placed? 1+1=2

(b) Name and describe the four basic types of constants
in C. 2
OR

10. (a) Why are some of the statements within a C program
indented? Why are empty lines included within a
typical C program? 1+1=2
(b) Name and describe the four data types qualifiers
in C. 2

11. Write the printf ( ) specifiers and flags with meanings in
C language. 4
OR
12. (a) In what ways does the control string within a
printf ( ) function differ from the control string within
a scanf( ) function? 2
(b) Distinguish between getchar ( ) and gets( )
functions. 2

UNIT—III
13. (a) What is a function? What is meant by the term
‘function call’? 1+1=2
(b) What is an array? Explain the declaration of one-
dimensional array with example. 1+2=3

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( 11 )

OR

14. (a) Write a program that will find the greatest number
in an integer array of user-defined size. 3
(b) What is the scope of a static variable? Give example.
1+1=2

15. (a) Explain the difference between parameter passing
mechanisms call by Value and call by Reference. 2
(b) How can a portion of an array be passed to a
function? 1
(c) Explain with an example how elements of an array
can be accessed by using a pointer. 2
OR
16. (a) What is a pointer? What is the relationship between
the data item represented by a variable var and the
corresponding pointer variable pvar? 1+1=2
(b) What is meant by dynamic memory allocation? 1
(c) Explain recursion with example. 2

UNIT—IV

17. (a) How does a structure differ from an array ? 1½
(b) What is the purpose of typedef feature? How is this
feature used with structures? 2
OR

18. (a) Differentiate between structure data type and union. 1½
(b) Write a note on enumeration. 2

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( 12 )

19. (a) Describe the use of arguments within a macro. 1½
(b) What is the principle advantage in the use of macro
rather than a function ? What is the principle
disadvantage? 2
OR

20. (a) What is the difference between r+ and w+ modes in
standard I/O? 1½
(b) What is the purpose of the fclose( ) function? 1
(c) What is the purpose of the fwrite( ) function? 1

  

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