Displacement:
Displacement is a vector quantity that represents the change in position of an object in a particular direction. It is the straight-line distance and direction between an initial and final point. While displacement can provide information about the change in position of an object, it does not directly indicate the direction of the net external force acting on the body. The net external force acting on an object is determined by considering all the individual forces acting on it.

Velocity:
Velocity is a vector quantity that describes the rate at which an object changes its position. It is defined as the rate of change of displacement with respect to time. While velocity can indicate the direction in which an object is moving, it does not necessarily represent the direction of the net external force acting on the body. The net external force acting on an object affects its velocity by changing its magnitude or direction.

Acceleration:
Acceleration is a vector quantity that measures the rate at which an object changes its velocity. It is defined as the rate of change of velocity with respect to time. Acceleration can be positive or negative, depending on whether the object is speeding up or slowing down. The direction of acceleration is determined by the net external force acting on the body. According to Newton's second law of motion, the acceleration of an object is directly proportional to the net external force acting on it and inversely proportional to its mass. Therefore, acceleration can indicate the direction of the net external force acting on a body.

Change in Momentum:
Momentum is a vector quantity that represents the motion of an object and is defined as the product of its mass and velocity. The change in momentum of an object is equal to the net external force acting on it multiplied by the time interval over which the force is applied. According to Newton's second law of motion, the rate of change of momentum of an object is equal to the net external force acting on it. Therefore, the direction of change in momentum is always in the direction of the net external force acting on the body.

Conclusion:
While displacement and velocity provide information about the motion of an object, they do not directly indicate the direction of the net external force acting on the body. On the other hand, acceleration and change in momentum can provide information about the direction of the net external force acting on the body.