Multi-choice problem: Continue writing the next sentence in this paragraph:

How to have healthy lips
Avoid licking your lips.
When you lick your lips it is usually in an attempt to moisturize them. However, saliva will actually just dry them out.

Options: a). Licking your lips is a natural thing to do, especially when they are dry, not chapped. You can help prevent dryness by blowing cool air on them.; b). In fact, not only does it dry out the surface, it also creates a lot of damaging friction on the lips. It can be hard to stop licking your lips when you do it subconsciously.; c). Your lips are going to dry out if you just lick them. This can happen after brushing your lips, when your lips are still damp from eating.; d). You will need to do a little research before you start doing this. You can, however, try to do something like wait a few minutes after eating before licking your lips.;
b).