which of the following graphs could represent an aging person with osteoporosis due to excessive bone reabsorbtion?

a
b
c
d

The correct answer should be option b.

Osteoporosis is a disease in which bones are weakened due to bone resorption. It occurs in old ages and increases the risk of breaking of bones.

Osteoblasts are the bone cells which are responsible for mineralization of the bone and thus it helps in the formation and strengthening of the bones.

The number of osteoblasts in an organism usually increases up to certain age.

It usually decreases when blood calcium level decreases and in old ages.

Thus, the graph made between age and number of osteoblast must be a bell-shaped graph. Hence, graph given in option b must be the correct one.

b brown mice / white sand dunes

thinking it would be physical characteristics