求教一道非常confuse的CR题

credo1992

Medical personnel who served in heavy combat in a recent war-even those who escaped physical injury-now have lower incomes and higher divorce rates, and score lower on psychological profiles measur-ing general happiness, than medical personnel who served in less stressful settings during that war. This evidence demonstrates that exposure to heavy-combat situations produces serious adverse effects, even among those who suffered no physical harm.
Which of the following, if true, most strengthens the conclusion drawn above?
(A) The medical personnel who served in heavy combat had completed significantly less schooling prior to military service than had other medical personnel.
(B) The medical personnel who served in heavy combat tended to be younger at the time of their entrysintosmilitary service than were other medical personnel.
(C) Parents of medical personnel who served in heavy combat show no significant difference in incomes, divorce rates, or general happiness from parents of other medical personnel.
(D) Income levels, divorce rates, and levels of general happiness are the same for the medical personnel who served in heavy combat as they are for construction workers.
(E) Medical personnel who served in heavy combat in an earlier war show no significant difference in incomes, divorce rates, or general happiness from other medical personnel who served in that war.

OA:C
我的分析：

条件：重战区医护人员既是没有受伤，也比执行不激烈作战任务的医疗人员收入低且离婚率高，心理也不好

结论：激烈战争中即使没有受伤，人也会受到负面影响

GAP：有其他原因导致重战区医疗人员心里不好，或者重战区其他人员心理没有问题，医护人员只是个例（因为题设是从医护人员的个体推及到整个重战区人群的整体）。

这么看我觉得C和D都是对的，因为D拿医护人员与建筑工人比较，就消除了 ：重战区其他人员心理没问题，医护人员只是个例这个GAP。为什么D不对呢...

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