Which of the following function prototypes is NOT valid? Select one: a. void doSomething(int& x, int y); b. void doSomething( int& x, int& y); c. void doSomething( int x, int y); d. void doSomething( int x, int y); e. All are valid.

For a prototype enumerated in any given program to be valid, it has to follow a specific format that is registered in the directory of commands of the programming language.
If the prototype fails to follow the guided format, the program would exhibit errors and may fail to run properly or may not at all run.
It is primarily necessary for a developer to take care of the entry of prototypes to avoid program failures.

Which of the following function prototypes is NOT valid? Select one: a. void doSomething(int& x, int y); b. void doSomething( int& x, int& y); c. void doSomething( int x, int y); d. void doSomething( int *x, int *y); e. All are valid.