P is a carboxylic acid having molecular formula $\text{C}_5\text{H}_{10}\text{O}_2$. When carboxylic acid P is reacted with an excess of LiAlH$_4$, compound Q is produced. Which pair of molecules could represent carboxylic acid P and compound Q?
- A1 and 2
- B1 and 3
- C2 and 3
- D3 only