For the recursive factorial function output shown below, which lines of output would reflect the backward phase? 1 factorial(3) 2 3 * factorial(2) 3 3 * 2 * factorial(1) 4 3 * 2 * 1 5 3 * 2 6 6 (1 point) Responses 1,2,3 1,2,3 1,4 1,4 4,5,6 4,5,6 1,2,3,4,5,6

Answer 1

To determine which lines of output reflect the backward phase of the recursive factorial function, we need to understand how the recursion works:

1. Forward Phase: This is when the recursive calls are being made. In this phase, the function calls itself with decremented values (n-1) until it reaches the base case (typically factorial(1) or factorial(0)).

2. Backward Phase: This is when the function starts returning values back through the recursion, multiplying the results together as it unwinds the stack of calls.

From the provided outputs:

• Lines 1, 2, and 3 are part of the forward phase as they are making recursive calls.
• Lines 4, 5, and 6 represent the backward phase where the multiplication results start being calculated and returned.

Therefore, the lines of output that reflect the backward phase would be 4, 5, 6.

So the correct response is 4,5,6.