Osteoporosis is caused by

Options

A. `Ca^(2+)` deficiency
B. `Na^(+)` deficiency
C. `K^(+)` deficiency
D. Parathormone hypersecretion.

Answer

**Step-by-Step Solution:**

1. **Understand Osteoporosis**: Osteoporosis is a medical condition characterized by decreased bone density, leading to weak and brittle bones. This makes bones more susceptible to fractures.

2. **Identify the Causes**: The question asks for the cause of osteoporosis. The options provided are:
- A) Calcium deficiency
- B) Sodium deficiency
- C) Potassium deficiency
- D) Parathormone hypersecretion

3. **Analyze Each Option**:
- **Option A: Calcium Deficiency**: This is incorrect. In osteoporosis, there is not a deficiency of calcium; rather, there is an increased level of calcium in the blood due to the reabsorption from the bones.
- **Option B: Sodium Deficiency**: This is also incorrect. Sodium does not play a direct role in the development of osteoporosis.
- **Option C: Potassium Deficiency**: This option is incorrect as well. Potassium levels do not directly influence bone density in the context of osteoporosis.
- **Option D: Parathormone Hypersecretion**: This is the correct answer. Parathormone (or parathyroid hormone) is secreted by the parathyroid glands and is responsible for regulating calcium levels in the blood. Hypersecretion of parathormone leads to increased reabsorption of calcium from the bones into the bloodstream, weakening the bones and leading to osteoporosis.

4. **Conclusion**: Based on the analysis, the correct cause of osteoporosis is parathormone hypersecretion.

**Final Answer**: Osteoporosis is caused by parathormone hypersecretion (Option D).

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