Three boys P,Q and R are to speak at a function along with 5 others. If all of them speak in random order, what is the probability that P speaks before Q and Q speaks before R?

Question

$( A ) \large\frac{1}{9} \\ ( B ) \large\frac{2}{3} \\ ( C ) \large\frac{1}{3} \\ ( D ) \large\frac{1}{6}$