WAEC 2020 · Paper 1 · Q11

The implication $x \Rightarrow y$ is equivalent to

Worked solution (try it first)

An implication $x$
$\Rightarrow y$ is equivalent to its contrapositive: swap the two parts and negate both.
So $x$
$\Rightarrow y$ is equivalent to $\sim y$
$\Rightarrow \sim x$ , option A.