Final answer:
The negative aspect of a Dihedral Wing is increased vulnerability to adverse yaw, where the aircraft experiences a yawing moment opposite to the direction of a turn.
Step-by-step explanation:
The negative aspect of a Dihedral Wing among the options provided is c) Increased vulnerability to adverse yaw. The dihedral angle on an aircraft's wing is the upward angle of the wings when viewed from the front of the aircraft. This design feature enhances the stability of the aircraft in roll, as in option a), and can help to reduce the susceptibility to Dutch Roll, a type of oscillatory motion, as indicated in option b). However, the increased angle of the wings can also make the aircraft more susceptible to adverse yaw, which is a yawing moment opposite to the direction of a turn, especially during maneuvers that involve rolling the aircraft. Option d), an enhanced lift-to-drag ratio, is generally not a characteristic associated with dihedral wings; actually, dihedral wings can cause a slight increase in drag.