Select the correct statement with respect to locomotion in humans :

Options

A. Accumulation of uric acid crystals in joints causes their inflammation .
B. The vertebral column has 10 thoracic vertebrae
C. The joint between adjacent vertebrae is a fibrous joint
D. A decreased level of progesterone causes osteoporosis in old people

Answer

To solve the question regarding locomotion in humans and select the correct statement, we will analyze each statement provided in the question step by step.

### Step-by-Step Solution:

1. **Statement 1: Accumulation of uric acid crystals in joints causes their inflammation.**
- This statement is correct. The accumulation of uric acid in the joints can lead to a condition known as gout, which is characterized by inflammation and pain in the joints due to the formation of uric acid crystals.

2. **Statement 2: The vertebral column has 10 thoracic vertebrae.**
- This statement is incorrect. The human vertebral column actually consists of 12 thoracic vertebrae, not 10.

3. **Statement 3: The joint between adjacent vertebrae is a fibrous joint.**
- This statement is also incorrect. The joints between adjacent vertebrae are classified as cartilaginous joints, which allow limited movement, rather than fibrous joints, which do not allow movement.

4. **Statement 4: Decreased level of progesterone causes osteoporosis in old people.**
- This statement is incorrect. Osteoporosis is primarily associated with a decrease in estrogen levels, especially in postmenopausal women. Progesterone does not have a direct role in causing osteoporosis.

### Conclusion:
Based on the analysis of the statements, the correct statement regarding locomotion in humans is **Statement 1**: "Accumulation of uric acid crystals in joints causes their inflammation."

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