Apatient with osteoporosis (reduced bone mass) may have a history of health issues. one issue could be
not enough skin exposure to the sun to make vitamin d.
weak ligaments.
an increase in the absorption of calcium in the digestive system.
weak tendons.

The answer is; not enough skin exposure to the sun to make Vitamin D

When the skin is exposed to the sun, the 7-dehydrocholesterol in the skin is converted to vitamin D. This vitamin then plays a vital role in the increased absorption of calcium from the gut. Calcium is essential for bone strength since it is significant in bone mineralization. Therefore, the lack of sunlight causes the secondary effect of osteoporosis.

i am positive it is c. condensing but i may be wrong