Choose the correct statement(s) about the leaving group in SN1 reactions of tertiary substrates.

1. AThe order of reactivity is $(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{I}>(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{Br}>(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{Cl}$.
2. B$(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{F}$ reacts faster than $(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{Cl}$ because the C-F bond is more polar.
3. CProtonating $(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{OH}$ with a strong acid makes the leaving group neutral $\mathrm{H}{}_2\mathrm{O}$ and greatly increases the rate.
4. D$(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{OTs}$ is more reactive than $(\mathrm{CH}{}_3){}_3\mathrm{C}-\mathrm{Br}$.