Solution

The correct answer is They can be virtual..

Key Points

• A constructor is a special member function in object-oriented programming that initializes an object when it is created.
• Constructors do not have return types, not even void.
• Constructors cannot be inherited; however, a derived class constructor can call the base class constructor.
• A constructor cannot be declared as virtual. This is because constructors are used to initialize objects, and the virtual mechanism in C++ is used for runtime polymorphism, which is not applicable to constructors.
• Copy constructors are called when an object is created and initialized with another object of the same class.

Additional Information

• Types of Constructors:
  • Default Constructor: A constructor that takes no arguments and initializes data members with default values.
  • Parameterized Constructor: A constructor that takes arguments to initialize an object with specific values.
  • Copy Constructor: A constructor that creates a new object as a copy of an existing object.
• Important Characteristics of Constructors:
  • Constructors have the same name as the class.
  • They are automatically invoked when an object of the class is created.
  • They can be overloaded to create multiple constructors with different parameter lists.
• Restrictions for Constructors:
  • Constructors cannot be virtual, as virtual functions are called after the object is fully created, while constructors are used for object creation.
  • Constructors cannot have return types.
  • Constructors cannot be static or constant.