Answer: Python Puzzler #1142

The answer is D. The program prints:

boop-ping
What the program prints
Checked by running the program for real.

Why?

join glues the items of a list together, putting ‘-‘ between each pair.

The code again

sounds = ["boop", "ping"]
print("-".join(sounds))

Try it: change one number in the program and predict the new output before you run it.