Which of the following bones is classified as a short bone?

A carpal bone is classified as a short bone due to its cuboidal shape and its role in providing stability and support while allowing for some limited motion in the wrist. Short bones are characterized by their roughly equal dimensions in length and width, which help in transferring forces and facilitating complex movements.

In contrast, long bones, such as the femur and humerus, are much longer than they are wide and are primarily involved in supporting weight and facilitating movement. The sternum, being a flat bone, serves a different purpose, providing protection and serving as an attachment point for ribs and muscles. Thereby, the carpal bones exemplify the characteristics of short bones effectively, making them the correct answer.