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

LNG carriers must maintain rigorous gas detection systems across all potential leak points. 46 CFR Part 154 mandates monitoring in barrier spaces, cargo handling rooms, and fuel supply piping to ensure early detection of methane, which is critical for preventing fire or explosion in cryogenic containment systems.