Q18: Which of the following most logically completes the argument?
Yorco and Zortech are two corporations that employ large numbers of full-time workers who are paid by the hour. Publicly available records indicate that Yorco employs roughly the same number of such hourly wage workers as Zortech does but spends a far higher total sum per year on wages for such workers. Therefore, hourly wages must be higher, on average, at Yorco than at Zortech, since _____.
- Zortech spends a higher total sum per year than Yorco does to provide its hourly wage workers with benefits other than wages
- the work performed by hourly wage workers at Zortech does not require a significantly higher level of skill than the work performed by hourly wage workers at Yorco does
- the proportion of all company employees who are hourly wage workers is significantly greater at Yorco than it is at Zortech
- overtime work, which is paid at a substantially higher rate than work done during the regular work week, is rare at both Yorco and Zortech
- the highest hourly wages paid at Yorco are higher than the highest hourly wages paid at Zortech
为什么选D啊!我想的答案应该是OVERTIME WORK 在Z很RARE在Y不一定RARE.但是两者都给予了否定,这怎么是好啊? | 
