Enthuware

I'm confused by the correct answer. The explanation under the correct answer says

and so the thread that removes "a" and "b", may remove them in any order. Thus, the iterator thread may or may not see "a" and/or "b" through its Iterator.

So wouldn't a more correct answer be "It may print any combination except "a," or "b," or "a, b, " or "b, a""?

I'm not sure this question really tests what you're trying to test, but I'm probably missing something here.

You are right. As the explanation says "c," will always be there the option does not capture all the invalid options.

Should be fixed.

thank you for your feedback!
Paul.