When I get my ballot with an uncontested seat, I can still choose whether to check the box. Even though it doesn’t impact the outcome at all, I still have the choice on whether to check the box. Even if I am completely restrained and my movements are forced, I still have the choice of whether to accept or resist that action, even if it’s just a mental protest.

So I don’t think there’s ever a case where there are no other options, but there are plenty of situations where there are no other good options (e.g. cake or death), but that doesn’t restrict your free will, it just restricts your options.