Answer: Python Puzzler #1771

The answer is B. The program prints:

59

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
12	yes	12
59	yes	59
40	no	59
5	no	59
28	no	59

The code again

numbers = [12, 59, 40, 5, 28]
biggest = 0
for n in numbers:
    if n > biggest:
        biggest = n
print(biggest)