Question

bones are composed mostly of ________.
a. magnesium
b. vitamins
c. calcium
d. cartilage
please select the best answer from the choices provided.
○ a
○ b
○ c
○ d

Explanation:

Bones are primarily composed of calcium (in the form of calcium phosphate and calcium carbonate) which gives them strength and rigidity. Magnesium is present in smaller amounts, vitamins are not a major structural component, and cartilage is a different connective tissue, not the main component of bones.

Answer:

C. calcium