Which scenario would least likely require a "pan-pan" call?

A "pan-pan" call is used in maritime communication to indicate urgent situations that require assistance but do not pose an immediate danger to life or vessel.

The scenario involving a person overboard is the least likely to require a "pan-pan" call because it is generally considered a situation of higher urgency. If someone has fallen overboard, immediate action to recover the person is vital. This scenario typically warrants a "mayday" call, which is reserved for distress situations where there is an imminent risk to life or health.

In contrast, the other scenarios—engine failure, near collision, and low fuel consumption—while they may be urgent, do not typically present an immediate threat to life and can often be managed without an immediate risk to human safety. Thus, they would be more appropriate for a "pan-pan" call.