Answer
Kinetic energy can never be negative.
It is possible for gravitational potential energy to be negative.
Work Step by Step
Kinetic energy is the energy related to an object's motion. If an object is moving, then the kinetic energy is positive. If an object is not moving, then the kinetic energy is zero. Since these are the only two possibilities, kinetic energy can never be negative.
Gravitational potential energy depends on an object's position relative to a position where the gravitational potential energy is zero. Since an object can be closer or farther from the zero position, it is possible for gravitational potential energy to be positive, zero, or negative.