Reduction

Question

A is Recursively Enumerable but not recursive and A reduces to B then which of the following can be true?

A) B is Recursive

B) B is Recursive Enumerable

C) B is Not RE

D) B is CFL

Comments

@Arjun :  sir then, is it " 'B' can be as hard as A or 'B' can be harder than 'A' . ?

if it is then, 'B' can be "RE but Not REC" too, or 'B' can be 'NOT RE' .

but how 'B' can be RE ?.

as if we consider 'B' as 'RE', then there exists a subset of 'REC' in RE.

 

where am i going wrong ?

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both B and C are correct.

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@utkarsh, did u get my point. Why B is correct ? See my response to Arjun sir