Your Bones At Birth, the Human Body Contains Over 270 Bones. However

Your Bones
At birth, the human body contains over 270 bones. However, as the body grows, some of these bones fuse together. The average adult body contains 206 bones. Together, these bones form the skeleton. The skeleton has many vital functions, including protecting internal organs, providing support, enabling movement, generating blood cells, storing calcium, and helping to regulate the endocrine system.
Although we only have one skeleton, it is divided into two major regions: the axial and the appendicular skeletons. The former refers to everything on the body's middle axis, such as the skull, sternum, and vertebrae, while the latter refers to the bones that make up the arms, legs, pelvis, and shoulder girdle. These bones include the femur, the tibia, the ulna, and the radius.
Bones are further classified according to their shape and function. The five classifications of bones are: long, short, flat, irregular, and sesamoid bones. Long bones include the fibula and tibia. The carpal bones in the wrist are examples of short bones. Flat bones are thin and curved and include the ribs, the sternum, and some skull bones. Irregular bones, such as the vertebrae and some facial bones, have complex shapes. Finally, sesamoid bones are small, round bones that form in tendons. There are sesamoid bones in the hands, wrists, and feet, but the most familiar sesamoid bone is the patella, or kneecap.
Question: Which word would best replace 'regulate' at the end of the first paragraph?

A) Replace
B) Supervise
C) Maintain
D) Adjust