Which two compounds are structural isomers of one another?
- A$\text{CH}_3\text{CH}_2\text{CH}_3$ and $\text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_3$
- B$\text{CH}_2{=}\text{CHCH}_3$ and $\text{CH}_3\text{CH}{=}\text{CH}_2$
- C$\text{CH}_2(\text{OH})\text{CH}_2\text{CH}_3$ and $\text{CH}_3\text{CH}_2\text{CH}_2\text{OH}$
- D$\text{CH}_3\text{CH}_2\text{CH}_2\text{COOH}$ and $\text{CH}_3\text{COOCH}_2\text{CH}_3$