A compound $\mathrm{X}$ with the molecular formula ${\mathrm{C}}_3{\mathrm{H}}_8\mathrm{O}$ can be oxidized to another compound $\mathrm{Y}$ whose molecular formula is ${\mathrm{C}}_3{\mathrm{H}}_6{\mathrm{O}}_2$. The compound $\mathrm{X}$ may be:

Which of the following is the best set of reagents to perform the above conversion?

In the above reaction, the product formed by:

Arrange the following alcohols in increasing order of their reactivity for dehydration reaction in acidic medium.