Which of the following operators cannot be overloaded in C/C++ ?

Answer: Structure reference (the member access operator '.') cannot be overloaded in C++.

Why: The C++ language forbids overloading the built-in member access operator '.' because it would break name lookup rules and object model assumptions. As an alternative for pointer-like behavior you can overload operator->. Other operators that cannot be overloaded include the scope resolution operator '::', the conditional operator '?:', and sizeof.

• Bitwise right shift assignment (>>=): Can be overloaded for user-defined types; typically implemented as operator>>=(...) (often as a member).

• Address of (&): Can be overloaded by defining operator& for a class to customize address-taking behavior.

• Indirection (*): Can be overloaded by defining operator*; commonly used for iterator-like or smart pointer types.

• Structure reference (.): Cannot be overloaded. Use operator-> to provide custom member access behavior for pointer-like classes.