问题详情

In the 160 years in which "handedness" has been studied we have learned quite a lot, but we still cannot precisely describe what causes humans______to use one hand over the other, or why human populations are______toward right-hand use rather than left-hand use.
A．infrequently… prejudiced
B．habitually… neutral
C．preferentially … biased
D．perennially … disinterested
E．invariably … indisposed请帮忙给出正确答案和分析，谢谢！