The diagram illustrates the molecular structure of the naturally occurring molecule cholesterol. Student X said that all seventeen carbon atoms in the four rings are in one plane. Student Y said that this molecule shows $cis$-$trans$ isomerism about the $\text{C} = \text{C}$ double bond. Which students are correct?
- Aboth X and Y
- Bneither X nor Y
- CX only
- DY only