Nice question, but as only one list of values ended with 0 it was easy to get the answer without checking anything else, so much easier than it looked at first sight.

If there had been two options with 0 at the end it might have tested whether people knew that count(ALL, expression) and count(expression) meant the same, or that count(constant) was the same as count(*), but as it was the answer could be got without any of that.