1 .When are people easy to catch a cold?

A. In spring or winter.
B. In spring or autumn.
C. In autumn or winter.

2. Why haven't scientists found a cure for the common cold according to the passage?

A. There are too many kinds of cold viruses for them to identity.
B. It is not economical to find a cure for each type of cold.
C. They believe people can recover without treatment.

3. What does the speaker say about the symptoms of the common cold?

A. They reveal the seriousness of the problem.
B. They indicate how fast the virus spreads.
C. They show our body is fighting the virus.

4. What do some scientists say about taking medicines for the common cold?

A. It helps us to recover much sooner.
B. It actually does more harm than good.
C. It causes damage to some organs of our body.