I think, THINK it's C: No TM exists
Let me explain why,
In the proof of non-recursivly enumerable langauges we have seen that for every RE language there exists a TM,
Here, L is actually a superset of all the possible TM on a. Therefore L' will be
universel set - set of all possible string over a for which a TM exists.
Therefore basically it will a non - recirsivly emumerable language. Which cannot be accepted by a TM.
But I am not sure of the fact that this might be a recursive language also which are closed under complement but then also we had a set of TM which accpted a set of strings therefore its a RE.
Please correct me if I am wrong, this is actually a very good question.
But I am pretty aure I am right :P ;)
