The answer is B. The program prints:
6 3

Why?
// divides and throws away the remainder: each friend gets 6 sweets. % gives the remainder: 3 sweets left over.
Trace table
A trace table follows the program step by step. Here’s this one:
| sum | answer |
|---|---|
| 39 // 6 | 6 |
| 39 % 6 | 3 |
The code again
sweets = 39
friends = 6
print(sweets // friends, sweets % friends)
Try it: change one number in the program and predict the new output before you run it.