In which header file is the NULL macro defined?

A. stdio.h

B. stddef.h

C. stdio.h and stddef.h

D. math.h

Correct Answer is :

C. stdio.h and stddef.h

Explanation

The macro "NULL" is defined in locale.h, stddef.h, stdio.h, stdlib.h, string.h, time.h, and wchar.h.