Scientists typically do their most creative work before the age of forty. It is commonly thought that this happens because aging by itself brings about a loss of creative capacity. However, a study has found that almost all scientists who produce highly creative work beyond the age of forty entered their fields late and less than a dozen years before their creative breakthroughs. Since creative breakthroughs by scientists under forty also generally occur within a dozen years of the scientists’ entry into the field, the study’s finding strongly suggests that the real reason why scientists over forty rarely produce highly creative work is not due to age but rather because most have spent too long in their fields.
In the argument given, the two portions in boldface play which of the following roles?
A The first is the position that the argument as a whole depends; the second is evidence that is advanced as part of that evidence.
B The first and second are both claims that have been advanced in support of a position that the argument as a whole opposes.
C The first is an explanation that the argument challenges; the second provides evidence in support of a competing explanation that the argument defends.
D The first is an explanation that the argument challenges; the second is evidence that has been used against an alternative explanation that the argument defends.
E The first is an explanation that the argument defends; the second is evidence that has been used to challenge that explanation. ANS:C
對答案沒有問題,我想問的是這句話"a study has found that almost all scientists who produce highly creative work beyond the age of forty entered their fields late and less than a dozen years before their creative breakthroughs."我一直覺得我沒辦法正確理解它的意思,由其是後半段"late and less than a dozen years before their creative breakthroughs",請大家幫我翻譯一下嚕,謝謝^_^ | 
