The correct answer is: C. neither a semicolon nor a comma
A preprocessor directive is a line of text that tells the preprocessor to do something before the compiler starts compiling the code. Preprocessor directives always start with a hash mark (#), and they can be followed by any number of arguments. The arguments are separated by spaces, and there is no punctuation at the end of the directive.
For example, the following directive tells the preprocessor to include the contents of the file header.h:
#include <header.h>
The following directive tells the preprocessor to define a macro called MY_MACRO:
#define MY_MACRO 10
Preprocessor directives are not part of the C language, so they do not need to be terminated with a semicolon or a comma.