We are interested in the weather because it＿＿＿＿　us so directly---what we eat, what we do, and even how we feel.

A．affects

B．benefits

C．guides

D．effects

连续刺激肌肉，每后一次刺激落在前一次收缩的舒张期内引起的复合收缩称为

A．无肌肉收缩
B．一次单收缩
C．一连串单收缩
D．不完全强直收缩
E．完全强直收缩