Question #N41

The research team found that the type of exercise people prefer, whether it’s vigorous or more moderate, influences the amount of sleep they need.  For example, the group who prefers vigorous exercise needs an average of 7 hours of sleep, while those who prefer moderate exercise tend to need 8.  This finding suggests that, when designing sleep-tracking devices for athletes,  ______ taking into account the type of training regimen athletes are following.

Which choice completes the text so that it conforms to the conventions of Standard English?
A. it would be most efficient for the devices to
B. the devices should
C. the devices are to
D. the devices ought to