Which pairs of reagents are suitable for preparing the ether in good yield by the Williamson method (SN2 on the alkyl halide)?

1. A$\mathrm{CH}{}_3\mathrm{ONa}$ and $(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{Br}$ to give $\mathrm{CH}{}_3-\mathrm{O}-\mathrm{C}(\mathrm{CH}{}_3){}_3$
2. B$(\mathrm{CH}{}_3){}_3\mathrm{CONa}$ and $\mathrm{CH}{}_3\mathrm{I}$ to give $\mathrm{CH}{}_3-\mathrm{O}-\mathrm{C}(\mathrm{CH}{}_3){}_3$
3. C$\mathrm{C}{}_2\mathrm{H}{}_5\mathrm{ONa}$ and $\mathrm{C}{}_2\mathrm{H}{}_5\mathrm{Br}$ to give diethyl ether
4. D$(\mathrm{CH}{}_3){}_3\mathrm{CONa}$ and $(\mathrm{CH}{}_3){}_2\mathrm{CH}-\mathrm{Br}$ to give isopropyl tert-butyl ether