Given ∑ = {a, b}, which of the following sets is not countable ?

GATE · 1997 · CS · Question 3 subparts

1. A.

   Set of all strings over ∑

2. B.

   Set of all languages over ∑

3. C.

   Set of all regular languages over ∑

4. D.

   Set of all languages over ∑ accepted by Turing machines

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