Muscles are attached to the skeletal structures by  

Options

A. connective tissue sheath
B. ligaments
C. tendons
D. all the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks how muscles are attached to skeletal structures. We need to identify the correct term that describes this attachment.

2. **Analyzing the Options:**
The options provided are:
- A) Connective tissue sheath
- B) Ligaments
- C) Tendons
- D) All of the above

3. **Explaining Each Option:**
- **A) Connective tissue sheath:** This refers to the dense connective tissue that surrounds the entire muscle, known as the epimysium. While it plays a role in muscle structure, it does not directly attach muscles to bones.

- **B) Ligaments:** These are fibrous connective tissues that connect bone to bone. They provide stability to joints but do not attach muscles to bones.

- **C) Tendons:** Tendons are cord-like structures that attach skeletal muscles to bones. They are crucial for transmitting the force generated by muscles to move the skeletal system.

- **D) All of the above:** This option suggests that all the previous options are correct, but based on the definitions, this is not accurate.

4. **Identifying the Correct Answer:**
The correct answer is **C) Tendons**, as they are specifically responsible for attaching muscles to skeletal structures.

5. **Conclusion:**
Therefore, muscles are attached to skeletal structures by tendons.

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