The output (X) of the logic circuit shown in figure will be

Options

A. `X=barbar(A)*barbar(B)`
B. `X=bar(A*B)`
C. `X=A*B`
D. `X=bar(A+B)`

Answer

C

Explanation

`X=barbar(AB) =A*B`(i.e. AND gat)
If the output X of NAND gate is connected to the input of NOT gate (made from NAND gate by joining two inputs) from the given figure then we get back an AND gate.