Final answer:
The correct description of our limb structure is: long bone, short bones, number of bones, and digits. Most limb bones are long, like the femur or ulna, while the wrist and ankle bones are short bones for stability.
Step-by-step explanation:
The structure of our limbs can be described as consisting of long bones, short bones, a set of bones (such as the carpals for the wrist and tarsals for the ankle), and digits (fingers and toes). Therefore, the correct answer to the structure of our limbs is: a) Long; short; number of bones and digits. Long bones are characterized by a shaft and two rounded ends; they are longer than they are wide and function primarily as levers when muscles contract. Most limb bones are long bones, such as the femur, tibia, ulna, and radius. However, there are exceptions like the patella, as well as the bones of the wrist and ankle which are considered short bones because they provide stability and support with limited movement.