Identical resistors are arranged in four combinations $P$, $Q$, $R$ and $S$ between terminals $X$ and $Y$. In descending order of combined resistance between $X$ and $Y$ (with the greatest first), what is the sequence?
- A$P \rightarrow S \rightarrow Q \rightarrow R$
- B$P \rightarrow S \rightarrow R \rightarrow Q$
- C$Q \rightarrow R \rightarrow S \rightarrow P$
- D$S \rightarrow P \rightarrow Q \rightarrow R$