Which of the following statements is FALSE?

Question

a) The first stage of a thunderstorm's development is the cumulus stage.
b) Warm air is less dense than cold air
c) The cumulus stage of a thunderstorm usually features heavy rains.

Answer 1

http://weathereye.kgan.com/expert/tstorms/stages.html

Looks like c) is the answer

Answer 2

thanks drwls