That's because the first and last carbon atoms cannot be branched to form an isomer . Therefore only the three middle carbon atoms can form isomers.
The answer is <span>B. nonpolar.
Polar molecules dissolve best in polar solvents while nonpolar molecules dissolve best in nonpolar solvents. </span>Oils are nonpolar. So, they will dissolve best in nonpolar solvents. If you put oil in some polar solvent, such as water, it will hardly dissolve.