A、The man can easily change his bad habit. B、The man has to change his views on smoking. C、The man has developed chronic disease

W: It looks like we are going to have a shower at any minute now.
M: I think so. Look at the clouds in the sky. Whenever they seem dark and low like this, you know it’s going to rain.
Q: What do we know about the clouds?

M: Doctors say I must give up smoking and drinking if I want to restore health. But you know a leopard can’t change its spot.
W: Yes. But research also says that a heavy smoker is rather apt to developing many chronic diseases, and some of which are killers.
Q: What does the woman mean?