21. ATM (Asynchronous Transfer Mode) is fundamentally a:
1. Circuit switching
2. Packet switching
3. Narrow band

Which of the above is/are correct?
(a) 1 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3

Answer: (b)

22. In 𝐶 ++, a container is
(a) A data structure composed of objects
(b) A holder object that stores and manipulates a collection of objects
(c) An object that contains housekeeping information
(d) An interface for binary search tree implemented as a class

Answer: (b)

23. There are three classes A, B and C. An object of class B is passed as a parameter to a method in class A. An object of class C is created in class B as private member. The relation between A, B and C are:
(a) B aggregates A, and C aggregates B
(b) B aggregates A, and C composed of B
(c) A aggregates B, and B is composed of C
(d) A is composed of B, and B aggregates C

Answer: (c)

24. There are two variables A and B. Variable A is used by several functions of program. Variable B’s value is changed in successive calls of a single function, in which it is declared.
1. A is global and static
2. B is local and static
3. A is global and external
4. B is local and external

Which of the above statements are correct?
(a) 1 and 3
(b) 1 and 4
(c) 2 and 4
(d) 2 and 3

Answer: (d)

25. Consider the following statements:
1. A pointer to a base class can point to an object of its derived class
2. A pointer to a derived class can point to an object of the base class
3. A base class pointer can access extra added members in a derived class
4. A base pointer cast into a derived pointer can access it fully

Which of the above statements are correct?
(a) 1 and 3
(b) 2 and 3
(c) 1 and 4
(d) 2 and 4

Answer: (c)

26. Array is a structured data type in C programming language. It may be defined as, a finite:
(a) Collection of data items, not necessarily ordered, but of the same data type
(b) Collection of data items, not necessarily ordered, but of different data type
(c) Ordered collection of data items of different data type
(d) Ordered collection of data items of the same data type

Answer: (d)

27. The average successful search time for sequential search on 𝑛 item is:

Answer: (a)

28. A binary tree of depth 𝑑 is a complete binary tree if:
1. Each leaf in the tree is either at level 𝑑 or at level (𝑑 −1)
2. For any node n𝑑 in the tree with a right descendent at level 𝑑 all the left descendents of n𝑑 that are leaves are also at level 𝑑

Which of the above statements is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (a)

29. A binary tree has 𝑛 levels and the root level is zero. Then the maximum total number of nodes will be:

Answer: (b)

30. A complete binary tree having 𝑛 leaf nodes has how many nodes of degree 2?

Answer: (b)