What kind of members can a class have in C++?

In C++, a class can have private, public, and protected members, which allows for a versatile and robust design of object-oriented programs.

Private members are only accessible within the class itself, ensuring encapsulation and restricting access from outside classes. This is crucial for maintaining the integrity of the data by preventing external entities from modifying it directly.

Public members, on the other hand, are accessible from anywhere in the code that has visibility of the class, allowing interaction with the class's instances. This is important for defining the interface through which other parts of the program can use the class.

Protected members are similar to private members but are accessible in derived classes. This provides a way to extend or modify the behavior of a class in subclasses while still keeping some data encapsulated from outside access.

Having the ability to define members with these three access specifiers allows for a finely-tuned control over how classes and the data they contain can be accessed and modified, promoting better software design principles like encapsulation and inheritance.

The other choices limit the members to only one type, which does not reflect the versatility C++ offers in defining class members.