ISRO2008-73

Question

We can make a class abstract by

• A. Declaring it abstract using the virtual keyword
• B. Making at least one member function as virtual function
• C. Making at least one member function as pure virtual function
• D. Making all member function const.

Answer 1

Answer is c)

A pure virtual function or abstract function in C++ is a virtual function for which we don’t have any implementation, we can only declare it......

A pure virtual function is implemented by classes which are derived from a abstract class...

Ref: https://msdn.microsoft.com/en-us/library/c8whxhf1.aspx