$X$ is recursive $\implies \bar X$ is also recursive.
$Y$ is r.e. but not recursive $\implies \bar Y$ is not even r.e.
$\bar X$ reduces to $W \implies $ $W$ is recursive or a super set of it.
$\bar Y$ reduces to $Z \implies $ $Z$ is not even r.e.
Correct Answer: C.
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