The involuntary muscles that cause the wave like contractions pushing food along the intestine are :

Options

A. striated muscles
B. skeletal muscles
C. smooth muscles
D. intercalated muscles

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the type of involuntary muscles responsible for wave-like contractions that push food along the intestine.

2. **Identifying the Types of Muscles**: There are three main types of muscles in the body:
- **Skeletal Muscles**: These are voluntary muscles that are under conscious control and are striated in appearance.
- **Cardiac Muscles**: These are involuntary muscles found only in the heart and have intercalated discs.
- **Smooth Muscles**: These are involuntary muscles found in various internal organs, including the intestines, and are not striated.

3. **Function of Smooth Muscles**: The smooth muscles in the walls of the intestines are responsible for a process called peristalsis. Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract.

4. **Conclusion**: Since the question specifically refers to involuntary muscles that facilitate the movement of food along the intestine through wave-like contractions, the correct answer is **smooth muscle fibers**.

5. **Final Answer**: The involuntary muscles that cause wave-like contractions pushing food along the intestine are **smooth muscle fibers**.

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