ALGORITHM S(n) //Input: A positive integer n //Output: The sum of the first n cubes if n = 1 return 1 else return S(n  1) + n  n  n A. What does this algorithm compute? B. What is its basic operation? C. Does the number of times of the basic operation executed depend on the nature of the inputs of the same size? D. Set up a recurrence relation for the number of times the algorithms basic operation is executed.