How is the center of gravity defined in an aircraft?

The center of gravity (CG) in an aircraft is defined as the point where all of the aircraft's weight is considered to be concentrated. This concept is crucial for understanding how the aircraft behaves during flight, as the location of the CG affects stability, control, and performance.

When the CG is properly positioned, it helps ensure that the aircraft is balanced, which facilitates smooth handling characteristics. If the CG is too far forward or too far aft, it can lead to challenges in pitch stability and control, impacting the aircraft's ability to fly efficiently.

The other options do not accurately capture the definition of the center of gravity. The point where the wings meet the fuselage does not reflect the distribution of weight across the entire aircraft. The point of maximum payload relates to weight capacity but does not define where weight concentration occurs. Lastly, the point of minimum drag pertains to aerodynamic performance rather than weight distribution, which is distinct from the center of gravity. Thus, option B is the most appropriate definition of the center of gravity in aviation.