Which of the muscles are attached to bones?
(a) Smooth muscles
(b) Skeletal muscles
(c) Cardiac muscles
(d) All the above

Options

A. Smooth muscles
B. Skeletal muscles
C. Cardiac muscles
D. All the above .

Answer

To determine which muscles are attached to bones, we need to analyze each option provided in the question.

1. **Smooth Muscles**:
- Smooth muscles are involuntary muscles that are uninucleate (having one nucleus).
- They are primarily found in the walls of internal organs (like the intestines, blood vessels, etc.) and are not attached to bones.
- Therefore, smooth muscles are **not** attached to bones.

2. **Skeletal Muscles**:
- Skeletal muscles are striated (having a banding pattern) and are known as voluntary muscles, meaning they can be consciously controlled.
- These muscles are multinucleate (having multiple nuclei) and are specifically designed to be attached to the skeletal system.
- Since skeletal muscles are directly attached to bones, they are the correct answer.

3. **Cardiac Muscles**:
- Cardiac muscles are also involuntary and multinucleate, but they are specifically found in the heart.
- They are not attached to bones, as their primary function is to pump blood throughout the body.
- Therefore, cardiac muscles are **not** attached to bones.

4. **All the Above**:
- This option suggests that all types of muscles (smooth, skeletal, and cardiac) are attached to bones.
- Since we have established that only skeletal muscles are attached to bones, this option is incorrect.

### Conclusion:
The correct answer is **(b) Skeletal muscles**, as they are the only type of muscle that is attached to bones.

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