W: Bob, I'm sure you know about second-hand smoke. M: Of course, I do. W: But have you heard about third-hand smoke? M: Third-hand smoke? I'm afraid not. What is that then? W: Well, it is here in today's paper. Parents may think they are protecting children from second-hand smoke when they smoke outside their home or only when the children are not there. But now researchers are warning about what they call third-hand smoke. When you smoke dangerous matter from cigarettes get into your hair and clothing. As babies are the weakest, when you come to a baby, you pass it to the baby and increase the chances of disease in the baby. M: Is that so? In that case I have to say that I should never get close to a baby. W: That's right. Actually all smoking parents should do the same or better give it up completely., Question: Why does the man say that he should keep away from babies? (A) He has just become a father. (B) He wears dirty clothes. (C) He is a smoker.
(C) He is a smoker.