Answer:
A.) I
Step-by-step explanation:
The first one is the most likely to be solid at room temperature because it is the only structure depicting a saturated fat.
Saturated fats have no double bonds between the carbons in the parent chain. This allows the molecules to assume very compact positions, causing it to be solid at room temperature.
Unsaturated fats have these double bonds which bend the structure. These "kinks" in the molecule are what make unsaturated fats liquid at room temperature.