Answer:
A leaf is falling from the tree.
Explanation:
If motion is in only one direction(x-direction) then it is know as one directional motion.
If motion is in only two direction (x and y directions) then it is know as two directional motion.
If motion is in only three direction (x , y and z directions) then it is know as three directional motion.
A bird is flying in the air -This is three directional motion.
A leaf is falling from the tree - This is two directional motion.
A train is running on track - This is one directional motion
A lady is crawling on the surface of the ball - This is three directional motion.
Therefore the answer is ---
A leaf is falling from the tree.
