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