Regarding the speed of sound in a gas, match the following:

$A$. Temperature of gas is made $4$ times and pressure $2$ times	$P$. Speed becomes $2\sqrt{2}$ times
$B$. Only pressure is made $4$ times without change in temperature	$Q$. Speed becomes $2$ times
$C$. Only temperature is changed to $4$ times	$R$. Speed remains unchanged
$D$. Molecular mass of the gas is made $4$ times	$S$. Speed becomes half

• A
  $A-P, B-R, C-Q, D-S$
• B
  $A-Q, B-S, C-Q, D-S$
• C
  $A-S, B-R, C-Q, D-S$
• D
  $A-Q, B-R, C-Q, D-Q$