A ball is thrown through the air. What condition(s) would enable the ball to continue in its state of motion? A. a tailwind
B. a headwind
C. no air resistance or gravity
D. contact with another object

C) No air resistance or gravity

Explanation:

For headwind imagine an airplane flying. The wind is hitting the front of the aircraft. Just like the wind is hitting the front of the ball. This increases the drag force and the ball will eventually slow and let the force of gravity act.

For tailwind imagine a sailboat. The wind catches the sail a pushes the boat. Both the wind and boat are going the same way so the angle of the wind is coming from behind. This is why it is called a tail wind.

If a ball is thrown, it has wind resistance and gravity. Otherwise just imagine the ball traveling all around the earth. Because the ball only has the force of lift and thrust, the ball will stay in motion until it hits something strong enough to counteract its thrust.

The description does not state any contact with another object. Also the ball will immediately stop if it has less newtons of force.

c. magnitude and direction