When subminimal stimulus given then `:-`

Options

A. Muscle contract vigorously
B. Muscle contract slowly
C. Muscle never contract
D. Muscle become fatigue

Answer

### Step-by-Step Solution:

1. **Understanding the Concept of Stimulus**:
- A stimulus is a signal that triggers a response in a muscle. In the context of muscle contraction, a stimulus must reach a certain level known as the threshold stimulus to initiate a contraction.

2. **Defining Subminimal Stimulus**:
- A subminimal stimulus is any stimulus that is below the threshold level. This means it is not strong enough to cause the muscle fibers to contract.

3. **Applying the All or None Principle**:
- According to the all or none principle, a muscle fiber will either contract fully when the threshold stimulus is met or not contract at all if the stimulus is below this threshold. There is no partial contraction.

4. **Conclusion**:
- Therefore, when a subminimal stimulus is applied to a muscle, the muscle will not contract at all. This leads us to conclude that the correct answer to the question is that the muscle will not contract.

### Final Answer:
When a subminimal stimulus is given, the muscle will not contract at all.

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