Which of the following statements is a valid abstract member function declaration for class Food?
A) abstract double percent_protein();
B) abstract double percent_protein() const = 0;
C) virtual double percent_protein();
D) virtual double percent_protein() const = 0;

Question

Quizplus · Accepted Answer

The correct choice is D) virtual double percent_protein() const = 0;. This is because in C++, an abstract member function (or pure virtual function) is declared by appending "= 0" to its declaration. The use of "const" indicates that the function does not modify any member variables of the class. The "virtual" keyword is necessary for polymorphism, allowing derived classes to provide their own implementation of the function.

Which of the Following Statements Is a Valid Abstract Member