What causes the air to spin?

a. Cold/dry air sinks below the warm/wet air and it is pushed upwards
b. The land around the tornado
c. A cloud reaches down from the sky
d. Warm/wet air sinks below the cold/dry air and it is pushed upwards

Respuesta :

Cold dry air sinks below the warm wet air and it pushed upwards
Letter (A.)
d because the dry air gets mixed with the warm and wet air and causes this to happen tornado