Answer:
The correct answer is - A. Report this as a serious adverse event (SAE).
Step-by-step explanation:
A serious adverse effect (SAE) is a condition that can cause a threat to the patient's life or functioning. As here the research site staff becomes aware and knows of a participant's death searching through public records it is called a serious adverse effect (SAE).
Thus, the correct answer is - A. Report this as a serious adverse event (SAE).