Which of the following is a reserved word in C++?

What are two personal character traits helpful to a freelance photographer?

What will be an ideal response?

To test whether a character is one of ‘0’, ‘1’, ‘2’, ‘3’, ‘4’, ‘5’, ‘6’, ‘7’, ‘8’, or ‘9’, use the _______ standard library function.

a. isnumber b. isnotalpha c. isnumeric d. isdigit e. all of the above