What device will be activated while loading a LNG tank and the HI-HI liquid level set point is reached?

Correct Answer: Option D — Emergency shutdown.

Under 46 CFR 154.560, reaching the HI-HI liquid level set point in an LNG tank automatically triggers the Emergency Shutdown (ESD) system. This safety mechanism closes the manifold valves and stops cargo pumps to prevent tank overfill and catastrophic structural damage.