As Priya says from her straight shoot line, that makes sense.

A MACRO CAN CALL ANOTHER MACRO WITH IN ITS DEFINITION, PRETTY MUCH LIKE IN FUNCTIONS.

#define sq(x) x * x; // finds square of 'x'
#define cu(x) sq(x) * x; // finds cube of 'x'

Here a macro calls another macro, which is strticly possible. The similarity in functions could look like this.

int sq(int x) { return ( x * x ); }
int cu(int x) { return ( sq ( x ) * x ); }

would be a valid equivalent set of statements that could do the same functionality as that of above macros.

Hope tha HELPS!!!