On a MODU, the locker or space containing the self-contained breathing apparatus must __________.

Correct Answer: Option A — be marked "SELF-CONTAINED BREATHING APPARATUS"

Regulatory standards under 46 CFR require lockers housing self-contained breathing apparatus to bear clear, conspicuous lettering reading "SELF-CONTAINED BREATHING APPARATUS" to ensure rapid identification and deployment by emergency response personnel during toxic gas releases or fires.