An LNG carrier has an approved type of gas detecting system to detect methane leaks in the __________.

Correct Answer: Option D — all of the above

46 CFR 154 mandates comprehensive gas detection systems on LNG carriers to monitor spaces where methane could accumulate. This includes cargo handling rooms, barrier spaces, and fuel supply piping areas. These systems provide critical early warning of leaks, allowing for immediate isolation and mitigation to prevent fire or explosion hazards.