A dust particle oscillates in air with a time period which depends on atmospheric pressure $P$, density of air $d$ and energy of the particle $E$, then time period is proportional to
(A)
$\begin{array}{ll}P^{-\frac{5}{6}} d^{\frac{1}{2}} E^{\frac{1}{3}} & \text { (B) } P^{\frac{1}{2}} d^{3} E^{-2}\end{array}$
(C)
$\begin{array}{ll}P^{-\frac{1}{3}} d^{\frac{1}{2}} E^{2} & \text { (D) } P^{-2} d^{-\frac{1}{2}} E^{-3}\end{array}$