• Datatypes - General Questions
11. 

Which of the following statements are correct?

  1. We can assign values of any type to variables of type object.
  2. When a variable of a value type is converted to object, it is said to be unboxed.
  3. When a variable of type object is converted to a value type, it is said to be boxed.
  4. Boolean variable cannot have a value of null.
  5. When a value type is boxed, an entirely new object must be allocated and constructed.

A. 2, 5
B. 1, 5
C. 3, 4
D. 2, 3

12. 

Which of the following is the correct ways to set a value 3.14 in a variable pi such that it cannot be modified?

A. float pi = 3.14F;
B. #define pi 3.14F;
C. const float pi = 3.14F;
D. const float pi; pi = 3.14F;
E. pi = 3.14F;

13. 

Which of the following statements are correct about data types?

  1. Each value type has an implicit default constructor that initializes the default value of that type.
  2. It is possible for a value type to contain the null value.
  3. All value types are derived implicitly from System.ValueType class.
  4. It is not essential that local variables in C# must be initialized before being used.
  5. Variables of reference types referred to as objects and store references to the actual data.

A. 1, 3, 5
B. 2, 4
C. 3, 5
D. 2, 3, 4

14. 

Which of the following are the correct way to initialise the variables i and j to a value 10 each?

  1. int i = 10; int j = 10;
  2. int i, j;
    i = 10 : j = 10;
  3. int i = 10, j = 10;
  4. int i, j = 10;
  5. int i = j = 10;

A. 2, 4
B. 1, 3
C. 3, 5
D. 4, 5

15. 

Which of the following statement correctly assigns a value 33 to a variable c?

byte a = 11, b = 22, c;

A. c = (byte) (a + b);
B. c = (byte) a + (byte) b;
C. c = (int) a + (int) b;
D. c = (int)(a + b);
E. c = a + b;