What type of data can compromise safety and the ability of the flight crew to control the aircraft?

Weight data is critical to the safety and control of an aircraft, as it directly affects the aircraft's performance, balance, and structural integrity during flight. Accurate weight data is essential for ensuring that the aircraft is operating within safe weight limits. If this data is inaccurate or compromised, it can lead to dangerous situations such as improper loading, which may result in the aircraft being overweight or improperly balanced.

Moreover, weight data influences essential calculations including takeoff and landing performance, fuel distribution, and overall flight dynamics. If the flight crew is unaware of discrepancies in weight records, they may not have the necessary information to make informed decisions regarding takeoff, in-flight operations, or landing. This lack of reliable data can significantly hinder the crew's ability to maintain control of the aircraft, potentially leading to safety risks.

In contrast, the other options, while important for various operational aspects, do not directly compromise the fundamental safety and control of the aircraft to the same extent. A passenger manifest is important for passenger safety and emergency procedures, cargo weight provides details on cargo load but is a subset of weight data, and a flight plan is critical for navigation and air traffic control but does not impact the aircraft's physical load directly like weight data does.