**Question: **The increasing order of the acidity of the $\alpha$-hydrogen of the following compounds is :

$(\mathrm{C})<(\mathrm{A})<(\mathrm{B})<(\mathrm{D})$

$(\mathrm{B})<(\mathrm{C})<(\mathrm{A})<(\mathrm{D})$

$(\mathrm{A})<(\mathrm{C})<(\mathrm{D})<(\mathrm{B})$

$(\mathrm{D})<(\mathrm{C})<(\mathrm{A})<(\mathrm{B})$

Correct Option: 4,

**Solution:**
$\mathrm{D}<\mathrm{C}<\mathrm{A}<\mathrm{B}$