When a trial ends at a site, the investigator has an obligation to submit a final report to the IRB/IEC. This is outlined in both ICH and CFR:

ICH E6(R2) 4.13: “Upon completion of the trial, the investigator should provide the IRB/IEC with a summary of the trial’s outcome.”

21 CFR 312.66: Requires investigators to “report to the IRB all changes in the research activity and all unanticipated problems involving risk, and to provide reports at the end of the study.”

The final report provides closure and documentation that the study was conducted ethically and in compliance with regulatory standards. Other documents listed in the options (monitoring reports, DSMB summaries, subject logs) may be retained by the sponsor or site, but they are not mandated for IRB submission.

Thus, the correct answer is A (Final Report). This ensures the IRB/IEC has an accurate record of study completion, outcome, and compliance with ethical oversight.