I think it are three separate questions a), b) and c)
That's what I initially thought as well. But the question states a regular expression, not regular expressions. It also means the teacher likes trick questions, as the answer to b) is any pattern that matches the empty string. It doesn't mean you're wrong - I just didn't find it likely.

In reply to Re^3: reg expression by JavaFan
in thread reg expression by bharatbsharma

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