单项选择题

当水平风的垂直切变达到(),水平切变达到()时,常有晴空湍流发生

A.1-2mps/100km    3-5mps/100m
B.1-2mps/100m     5-6mps/100m
C.1-2mps/100m    5-6mps/100km
D.1-2mps/100km   5-6mps/100m