According to the BSRs, when must all student jumps be completed?

The correct answer is that all student jumps must be completed by sunset. This regulation is in place primarily for safety reasons, as daylight conditions are critical for ensuring visibility during both the jump and the landing. Adequate daylight contributes to a clearer understanding of the jump area, landing zone, and potential hazards, which is especially important for students who are still developing their jump techniques and situational awareness.

Completing jumps by sunset also allows sufficient time for debriefing and addressing any issues immediately after the jump while there is still light. This is important for effective training and improvement. Furthermore, flying conditions can change significantly as the sun sets, impacting safety and visibility.

While the other options might seem logical, they do not align with the established guidelines regarding student jumps. For example, requiring jumps to be completed within one hour of arrival or by noon does not ensure optimal light conditions for safety and training continuity. Moreover, jumps being completed before the jumpers' briefing does not align with the necessary sequence of events during a jump day. All student jumps ideally should be executed while there is still daylight remaining, making the completion by sunset the most appropriate guideline.