Which of the following bones is the largest in the upper arm?

The largest bone in the upper arm is the humerus. This bone is critical for the structure and function of the arm, extending from the shoulder to the elbow. Its size and strength provide the necessary support for the muscles of the arm, which are responsible for movement and stability.

The humerus plays a key role in various activities, including lifting, throwing, and pushing. It has an upper end that connects to the scapula at the shoulder joint and a lower end that connects to the radius and ulna at the elbow joint. Its length contributes to a greater range of motion in the arm, making it crucial for many everyday functions.

In comparison, the radius and ulna are bones of the forearm, situated below the elbow and are smaller in size than the humerus. The clavicle, often referred to as the collarbone, is also not a bone within the upper arm itself; rather, it connects the arm to the body at the sternum and is positioned above the humerus. Thus, none of these bones can match the humerus in terms of size and role within the upper arm.