Which bones are included in the arm?

The arm is specifically defined as the region that extends from the shoulder to the elbow, comprising three main bones: the humerus, radius, and ulna.

The humerus is the single, large bone of the upper arm that connects the shoulder to the elbow. The radius and ulna are the two long bones in the forearm, which extend from the elbow to the wrist. Together, these three bones facilitate a wide range of movements and provide structural support to the upper limb, enabling functions such as lifting, throwing, and grasping.

Other options include bones that are involved in different anatomical areas. The first option includes the carpals, which are wrist bones, and does not pertain to the arm specifically. The third option lists the scapula and clavicle, which are part of the shoulder girdle, not the arm itself. The last option contains bones of the lower leg, which are entirely unrelated to the arm. Each of these options highlights structures important to other regions of the body, clarifying why the correct answer explicitly includes the three essential bones that constitute the arm.