In accordance with the ICH E2A Guideline, the sponsor must report an adverse event that...

Serious adverse events are subject to expedited reporting requirements.

ICH E2A 3.2.2:“Fatal or life-threatening unexpected ADRs should be reported as soon as possible but no later than7 calendar daysafter first knowledge.”

ICH E2A 3.2.3:Other serious unexpected events must be reported within 15 days.

Thus, the 7-day rule applies tolife-threatening and unexpected events(as in this case).

Correct answer:B (7 days).