Let A and $B$ be languages over an alphabet $.$ Let $f$ be a reduction from $A$ to $B.$

Then which of the following are true? $($Check all correct options to get credit$).$

$f$ is a C$++$ function

$f$ is a function that can be computed by some Turing machine.

For all string xin${}^{**},$ if xinA then $f(x)inB$

For all string $x,$ if $x!$inA then $f(x)!$inB

For all string xin${}^{**},$ if xinB then $f(x)inA$

$f$ is a Turing machine

$f$:${}^{**}{}^{**}$