Final answer:
The medication that is a preparation of a hormone produced by the thyroid gland used to treat bone loss is calcitonin.
Step-by-step explanation:
The medication used in treating bone loss that is a pharmacologic preparation of a hormone produced by the thyroid gland is calcitonin. This hormone helps regulate calcium and bone metabolism, and pharmaceutical preparations of calcitonin can reduce osteoclast activity, which helps in managing conditions such as osteoporosis. Other medications like alendronate and raloxifene are not derived from thyroid hormones but have different mechanisms in treating bone loss. Alendronate is a bisphosphonate that slows down bone breakdown, and raloxifene is a selective estrogen receptor modulator (SERM) with estrogenic effects on bone. Option 4, teriparatide, is a recombinant form of parathyroid hormone, not a thyroid hormone, and helps stimulate bone formation.