Answer: Python Puzzler #3825

The answer is D. The program prints:

48

This answer was checked by running the program for real.

Why?

The loop remembers the biggest number it has seen so far, and replaces it whenever it finds a bigger one. This is how computers find the maximum.

Trace table

A trace table follows the program step by step. Here’s this one:

n	n > biggest?	biggest
32	yes	32
37	yes	37
48	yes	48
2	no	48
19	no	48

The code again

numbers = [32, 37, 48, 2, 19]
biggest = 0
for n in numbers:
    if n > biggest:
        biggest = n
print(biggest)