Question

question 30
what biomineral constitutes vertebrate bones?
calcite - caco₃
chert - sio₂
apatite - ca(po₄)₃
pure carbon

Explanation:

Vertebrate bones are mainly composed of a form of apatite - hydroxyapatite which has a similar structure to $Ca(PO_4)_3$. Calcite is a common carbonate mineral not in bones, chert is a silica - rich rock, and pure carbon is not a major component of bones.

Answer:

Apatite - $Ca(PO_4)_3$