_________ joint is present in the region where arm is joined to the shoulder.

Answer

**Step-by-Step Solution:**

1. **Identify the Joint Location**: The question asks about the joint in the region where the arm is joined to the shoulder.

2. **Understand the Structure**: The shoulder joint is structured like a socket that allows the arm to fit into it. This structure resembles a cup.

3. **Determine the Type of Joint**: Since the arm fits into the shoulder like a ball fits into a cup, this type of joint is known for its ability to allow movement in multiple directions.

4. **Name the Joint**: The specific name for this type of joint is the "ball and socket joint." It allows for a wide range of motion, including rotation.

5. **Conclusion**: Therefore, the correct answer to the question is "ball and socket joint."

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