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

A

$$(D) < (C) < (A) < (B)$$

B

$$(B) < (C) < (A) < (D)$$

C

$$(A) < (C) < (D) < (B)$$

D

$$(C) < (A) < (B) < (D)$$