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There are some steps you can take yourself to avoid catching a cold. Contrary to popular belief, colds are not caused by exposure to severe weather. Colds are caused by viruses (病毒) harbored in the body, and you’ re better off out on the ski slopes or even waiting for the bus on a snowy day than you are in a warm room, surrounded by friends, co-workers, or fellow students, who just may be passing the viruses around. If you feel a chill when you’ re coming down with a cold, you’ re already sick. A chill is an early symptom: it’ s the cold that caused the chill, not the other way around.
While the virus can spread through droplets(飞沫) propelled into the air when a cold-sufferer coughs or sneezes. Surprisingly, this is not the most common mute of transmission. Numerous studies have now shown that the overwhelming majority of colds are "caught" by hand contact. A cold sufferer rubs her nose, thereby transferring the virus to her hand.
A. shake hands with our friends instead of kissing them
B. never touch the telephones, towels or plates
C. often wash our hands
D. often rub our noses and eyes