The correct options are
A It represents weight of the body.
B It represents forces acting on the body.
C It represents forces applied by the body.
Free-body diagram is a graphical illustration used to show the relative magnitude and direction of all forces applied on an object by the surrounding as well as forces applied by the object on the surrounding in a given situation. Since the weight of the body is also a force, it is also represented in the free body diagram. Forces acting on a body are represented by arrows. The direction of the arrow shows the direction of the force.