Five years ago, during the first North American outbreak of the cattle disease CXC, the death reate from the disease was 5 percent of all reported cases whereas today the corresponding figure is over 18 percent. It is clear, therefore, that during these 5 years, CXC has increased in virulence.
答案是:Since the first outbreak, farmers have learned to treat mild cases of CXC and no longer report them to veterinarians or authorities.
Agree with An. Assumption and support are not the same. Assumption is hidden in the argument, while support always gives new information. You can argue that assumption defintely "support" the argument because without it the argument will not hold. But in GMAT, they are two different subjects.
以下是引用mindfree在2003-9-11 0:04:00的发言: Agree with An. Assumption and support are not the same. Assumption is hidden in the argument, while support always gives new information. You can argue that assumption defintely "support" the argument because without it the argument will not hold. But in GMAT, they are two different subjects.