6) C

This is rather a simple question. You must have seen a similar diagram in AS biology in the cell membrane topic.

The tail is always hydrophobic (hydro-water and phobic-fear; so hydrophobic means it does not like water), meaning it does not like to get in contact with water. Hydrophilic means it can react with water.

The head of the head of the molecule shown is always hydrophilic and the tail is always hydrophobic.

So, the answer is C.