c
It is Williamson's synthesis. It involves the nucleophilic attack of alkoxide ion on alkyl halide according to \({S_{{N^2}}}\) mechanism. In order to prepare methyl tertiary butyl ether, we must use methyl halide (primary) and sodium tertiary butoxide, but not sodium ethoxide and \(t-\) alkyl halide because the latter undergoes elimination reaction rather than substitution