OG 101

101. Even though the direct costs of malpractice disputes amounts to a sum lower than one percent of the $541 billion the nation spent on health care last year, doctors say fear of lawsuits plays a major role in health-care inflation.fficeffice" />

(A)     amounts to a sum lower

(B)     amounts to less

(C)     amounted to less

(D)     amounted to lower

(E)         amounted to a lower sum

The correct choice must feature a verb that agrees with the plural noun costs and refers to an action completed last year (past tense). The verb amounts in A and B fulfills neither condition, and amounts to a sum in A is redundant. The same redundancy occurs in E, and the construction a lower sum than is awkward and imprecise in the context of the sentence. In D, the adjective lower is erroneously used in place of the noun less as object of the preposition to. Choice C is best.

还是没有明白为什么不能选D

感觉是形容词而不是名词。

amount to： to reach a total, especially a large total

During 1981 - 2, three instalments were issued amounting to more than 2000 pages.

less作名词时，意为“较少的数目”；后面的than one percent of the $541 billion应该是修饰它的定语吧！

请牛人指正！