A common complaint for people each year is catching a colD.Many uncomfortable symptoms accompany a colD.Each year, cold sufferers spend millions to【71】______this recurring problem. Any of two hundred different【72】______could cause a colD.Even though our bodies may become【73】______to a certain cold virus this winter, by next winter our antibodies will probably not recognize it. However, rhinoviruses account for 40% of the colds we catch. Treating that family of viruses would drastically decrease the number of colds we catch each year. Some scientists are now suggesting【74】______the body's immune responses rather than the virus itselF.One researcher suggests that to find a cure for colds we must weaken our immune system's【75】______. (31)
A.(31)
【参考答案】
combat combat 解析：参见第一段第四行。combat this recurring problem“......