I can't believe I have to actually explain this. You simply, either, select different personal questions (ones where the answers aren't known or can be easily figured out), or you don't put people's actual/true names down, but rather just about anything else, even a random set of keyboard characters. Yahoo doesn't care if the answers are true or not. Then jot it down somewhere so you'll have it if ever needed.
As if we don't know that, and as if we really care about your silly issue here.