Final answer:
The left forearm consists of the ulna and radius bones.
Step-by-step explanation:
The left forearm consists of two bones: the ulna and the radius. The ulna is the larger of the two, running parallel to the radius. It forms the inner part of the forearm. The radius is smaller and located on the outer side of the forearm. Both bones play a crucial role in the movement of the forearm and hand.