The correct option is A) work.
Work is said to be done by a force when a force is exerted on an object and the the object on which the force is exerted moves in the direction of the force.
The amount of work done is given by the product of the force and the displacement made by the object.
Option (B) is incorrect, since Watt is the unit of power.
Option (C) is wrong, since joule is the unit of work or energy.
Option (D) is wrong, since power is the rate at which work is done.