A string that is a formal parameter can be declareda.An array with empty bracesb.A pointer to characterc.Both A and Bd.None of the above

The correct answer is c. Both A and B.

In C programming, a string can be declared as an array with empty braces or as a pointer to a character.

Here's why:

a. An array with empty braces: In C, a string is essentially an array of characters. So, you can declare a string as a formal parameter using an array with empty braces. For example: void function(char str[]).

b. A pointer to character: A string can also be represented as a pointer to a character. This is because the name of an array is a pointer to the first element of the array. So, you can also declare a string as a formal parameter using a character pointer. For example: void function(char *str).

So, both of these methods are valid ways to declare a string as a formal parameter in C.