Seating Arrangements

Concept:Arranging persons in a linear order based on relative positions.Explanation:From "Q is left of R but on the right of P": $P$ is left of $Q$, and $Q$ is left of $R$. So $P, Q, R$ in that order.From "S is to be right of R and left of T": $R$ is left of $S$, and $S$ is left of $T$. So $R, S, T$ in that order.Combining: the full order left to right is $P, Q, R, S, T$.Thus the extremes are $P$ (leftmost) and $T$ (rightmost).Answer:P and T, which corresponds to option A.