Given the function prototype and variable declarations, which of the following is a valid function call?

void compute (int, float, char&, int& ); // function prototype

int x, y; //variable declarations
float p, q;
char r, s;

a) compute (x, 7.3, ‘c’, y);
b) compute (y, p, s, x + y);
c) compute (5, p + q, r, y);
d) compute (x , s, r, 8);

c) compute (5, p + q, r, y);