Technician a Says That Wet Cell Battery Gassing Produces an Explosive

Multiple Choice

Technician A says that wet cell battery gassing produces an explosive mixture of hydrogen and oxygen and that great care should be taken any time a battery is being charged.Technician B says that gassing occurs only during battery discharge cycles on maintenance-free batteries.Who is correct?

A) Technician A
B) Technician B
C) Both technicians A and B
D) Neither technicians A nor B