Consider the following function definition: void tripler(int& n) n = 3 * n; In a main program, assume we have the following items defined: int a[3] = {4,5,6}; int number = 2; Which of the following lines are acceptable function calls? Select all that apply a) tripler(a[number]); b) tripler(number); c) tripler(a); d) tripler(a[2]); e) tripler(a[3]);