The diagram illustrates a simplified structure of coenzyme $\text{Q}_{10}$. Which row gives the correct description of the structure of coenzyme $\text{Q}_{10}$?
- Athe coenzyme is an aldehyde; number of $\pi$ bonds in one molecule is $n + 2$
- Bthe coenzyme is an aldehyde; number of $\pi$ bonds in one molecule is $n + 4$
- Cthe coenzyme is a ketone; number of $\pi$ bonds in one molecule is $n + 2$
- Dthe coenzyme is a ketone; number of $\pi$ bonds in one molecule is $n + 4$