$P,\;Q,\;R,\;S,\;T\;and\;U$ are seated around a circular table, $R$ is seated two places to the right of $Q,P$ is seated three places to the left of $R,S$ is seated opposite $U$. If $P$ and $U$ now switch seats, which of the following must necessarily be true?
- $P$ is immediately to the right of $R$
- $T$ is immediately to the left of $P$
- $T$ is immediately to the left of $P$ or $P$ is immediately to the right of $Q$
- $U$ is immediately to the right of $R$ or $P$ is immediately to the left of $T$