Some … studies indicate that among F artists the rate of G and H(G and H)均为病 are 10 to 13 times as prevalent as in the population at large. 焦点集中在B和E. B, the rates of G and H are 10 to 13 more prevalent than in E, B and C are 10 to 13 times more prevalent than in 参考答案为E, 我认为应该是B. B, E再语法上均没有错,但是E再逻辑上有问题。如果选E,则表示F艺术家中得G and H病的人数比整个population的这两种病的人数要大10 到13倍。这是一个明显的错误。这有可能后者比前者大,in terms of incidence of G and H.
You may not notice that "the rate" ,in B,cannot be used with such an adjective as "prevalent",so a noun ,as the name of sickness in E, is required to be the subject of the subordinate clause. By comparing the degrees of prevalence of the sickness between artists and the whole population, we can know that there are more patients with such disease among artists propotionally than in the population at large.So i think the logic error you mentioned above is not existed.
a quick feedback. I have just checked "prevalent" in MW, prevalent means widespread. your answer is convincing. thanks a lot.
for another question, I have read your comments, you may notice I said thanks for short. However, what I am not sure is whether "A of B, V+ing modify A instead of B" is a conventional or just a idiosyncratic usage.
At least it seems to me, it is a conventional usage on which we should place emphasis not only when dealning SC, but also when processing sentences in writing.