You have a tow of chemical barges. The mate reports an ammonia smell around the head of the tow. You would suspect a leak in the barge carrying __________.

Correct Answer: Option C — morpholine

Morpholine is a chemical compound containing nitrogen that, when degraded or leaked, releases ammonia-like odors. In the context of chemical barge transport, identifying specific cargo characteristics is essential for safety. Other listed chemicals like heptane or propanolamine do not possess the distinct ammonia-like scent profile associated with morpholine leaks.