Man's elbow can only move forward not backward, because it has.

Options

A. Gliding Joint
B. Hinge Joint
C. Saddle Joint
D. Pivot joint

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that the man's elbow can only move forward and not backward. We need to identify the type of joint that allows this specific movement.

2. **Identifying Joint Types**: The options given are gliding joint, hinge joint, saddle joint, and pelvic joint. We need to analyze each type of joint to see which one fits the description of the elbow's movement.

3. **Analyzing the Hinge Joint**: The hinge joint allows movement in one plane only, which means it can flex (move forward) and extend (move backward) but not rotate. This is the type of joint found in the elbow. Therefore, the elbow can only move in one direction (forward) and cannot move backward.

4. **Eliminating Other Options**:
- **Gliding Joint**: This joint allows for sliding movements and is found in the wrist and spine. It does not fit the elbow's movement.
- **Saddle Joint**: This joint is found between the carpal and metacarpal of the thumb and allows for a greater range of motion but is not applicable to the elbow.
- **Pelvic Joint**: This is not a specific type of joint relevant to the elbow's movement.

5. **Conclusion**: After analyzing the options, we conclude that the elbow is a hinge joint, which allows movement only in one direction (forward) and not backward.

**Final Answer**: The man's elbow can only move forward, not backward, because it has a **hinge joint**.

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