冰岛冬季气温相对较温和的主要原因是

A．太阳辐射丰富

B．纬度位置较低

C．受极地东风影响

D．受暖流影响

Which part on the wave deflection corresponds to ventricular muscle repolarization in the following ECG graph()

A. A

B. B

C. C

D. D