求解1逻辑题：附题cd gwd 8-31（即gwd 2-12')

因为搜索结果无法查到，所以只好发帖麻烦大家……

Which of following most logically completes the argument?

Y and Z are two companies that employ large numbers of full time workers who are paid by the hour. Publicly avaiable records indicate that Y employs roughly the same number of such hourly wage workers as Z does but spends a far higher totalsum per year on wages for such workers.

Therefore, hourly wages must be higher, on avergae, at Y than at Z, since _________

D. Over time work, which is paid at a substantially higher rate than work done during the regular work week, is rate at both Y and Z,为什么这个选项是正确的呢？？