The answer is E. Lick.
The other four words are all actions that are involved in the process of eating. Taste is the sensation that is produced when food comes into contact with the taste buds on the tongue. Chewing is the process of breaking down food into smaller pieces so that it can be swallowed. Swallowing is the act of moving food from the mouth to the stomach. Gulping is a type of swallowing that is done quickly and without chewing.
Licking is not an action that is involved in the process of eating. It is an action that is used to apply a substance to a surface, such as when a dog licks its fur or a cat licks its paws.