Make correct pairs from the below-mentioned $X$ and $Y$:

$X$	$Y$
$1.$ Dehydrating agent	$p.$ Sulphur dioxide gas
$2.$ In preparation of firecrackers	$q.$ Concentrated sulphuric acid
$3.$ Weak bleaching agent	$r.$ Dihydrogen gas
$4.$ Lightest gas	$s.$ Sulphur

• A
  $(1-r), (2-q), (3-s), (4-p)$
• B
  $(1-q), (2-p), (3-s), (4-r)$
• C
  $(1-s), (2-q), (3-p), (4-r)$
• D
  $(1-q), (2-s), (3-p), (4-r)$