Methylmagnesium bromide, $\mathrm{CH}{}_3\mathrm{MgBr}$, evolves methane by acid-base reaction (ignore any addition reactions) with which of the following?

$\mathrm{CH}{}_3\mathrm{MgBr}$ acts as $\mathrm{CH}{}_3{}^{-}$, whose conjugate acid methane has $\mathrm{p}{K}_a\approx 48$. It deprotonates any acid stronger than that: ethanol (15.9), benzoic acid (4.20) and a terminal alkyne (about 25). Diethyl ether has no acidic hydrogen and does not release methane.