Which type of respiratory protection is preferable for repair/investigation personnel on a MODU in a hydrogen sulfide (H2S) environment?

A
U.S. Navy Oxygen Breathing Apparatus (OBA)
B
Emergency Escape Breathing Apparatus (EEBA)
C
Demand Self-Contained Breathing Apparatus (SCBA)
D
Pressure-Demand Self-Contained Breathing Apparatus (SCBA)
E