The bones become brittle in aged people due to  

Options

A. increased organic material
B. decreased organic material
C. increased inorganic material
D. decreased inorganic material

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why bones become brittle in aged people. This is a common condition that can affect the elderly.

2. **Identifying Key Factors**: As people age, their bodies undergo various changes, including changes in bone density and composition.

3. **Role of Calcium and Phosphate**: Bones are primarily made up of organic material (like collagen) and inorganic material (like calcium and phosphate). Calcium and phosphate are essential for maintaining bone strength.

4. **Bone Reabsorption**: In older individuals, the body tends to reabsorb calcium and phosphate from the bones rather than maintaining these minerals in the bone structure. This process can lead to a decrease in bone density.

5. **Condition of Osteoporosis**: The condition that arises from this loss of bone density is known as osteoporosis. Osteoporosis makes bones weaker and more prone to fractures.

6. **Conclusion**: Since the question is about why bones become brittle, the answer is that the bones lose inorganic material (calcium and phosphate), leading to brittleness. Therefore, the correct answer is "decreased inorganic material".

### Final Answer:
The bones become brittle in aged people due to **decreased inorganic material**.

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