A boy while playing under a mango tree saw a mango falling in front of him. This is due to the force of:
gravity
The force due to which any matter is attracted towards the centre of the Earth is known as the force of gravity. Here the mango falls due to the force of gravity. The force of gravity is exerted by the Earth on mango. Once, the mango gets detached from its branch, the mango falls down due to gravity (Downwards pull). In fact, any object which is thrown upwards, after sometimes, falls down due to gravity.