XDF SECTION13 Q15

Some psychiatric studies indicate that among distinguished artists the rates of manic depression and major depression are ten to thirteen times as prevalent as in the population at large.

(A) the rates of manic depression and major depression are ten to thirteen times as prevalent as in
(B) the rates of manic depression and major depression are ten to thirteen times more prevalent than in
(C) the rates of manic depression and major depression are ten to thirteen times more prevalent when compared to
(D) manic depression and major depression are ten to thirteen times as prevalent when compared to
(E) manic depression and major depression are ten to thirteen times more prevalent than in
 

答案是E.我选了B.想问一下倍数的表达有哪些形式呢?我不太懂,希望大家多多指教