Methylated spirit is

Which of the following alcohols is the most acidic?

Which of the following is incapable of showing the iodoform test?

An alcohol $X$ $(C_4H_{10}O)$ on dehydration gives an alkene $(C_4H_8)$ as the major product,which on bromination followed by treatment with $Y$ gives an alkyne $C_4H_6$. The alkyne $C_4H_6$ does not react with sodium metal. What are $X$ and $Y$?

Which of the following orders is correct regarding the boiling point?

Dehydration of an alcohol $(A)$ gives an alkene. Ozonolysis of one molecule of this alkene yields two molecules of acetaldehyde. Identify the alcohol $(A)$.