Assignment

[bigfisherman]

no , case does not matter for this assignment

[PanGalactic]

BTW, lines 21-25 are not calling functions. Those look like function declarations.

[filipe]

Notice that this:

(questions != 'a' && questions != 'b' && questions != 'c' && questions != 'd')

could be expressed more cleanly as:

(questions < 'a' || questions > 'd')

[Browni3141]

It's worse than being clean. The former will always be evaluated as false.
Oops, I was mistaken.

Since the user can still enter uppercase letters, you should convert their input to lowercase.

[hanst99]

The former will always be evaluated as false.

Actually, it will only be false when the user inputs something valid.