As functioning of smooth muscles can't be directly controlled, they are  

Options

A. voluntary
B. intermediate
C. involuntary
D. none

Answer

To answer the question "As functioning of smooth muscles can't be directly controlled, they are:", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Types of Muscles**:
- There are three main types of muscles in the human body: smooth muscles, skeletal muscles, and cardiac muscles.

2. **Understand Smooth Muscles**:
- Smooth muscles are found in various organs such as the esophagus, stomach, intestines, blood vessels, and iris of the eye.

3. **Control Mechanism of Smooth Muscles**:
- Smooth muscles are not under voluntary control, meaning they cannot be consciously controlled by an individual. Instead, their functioning is regulated by the autonomic nervous system.

4. **Define Voluntary vs. Involuntary Muscles**:
- Voluntary muscles (like skeletal muscles) can be controlled by our will, while involuntary muscles (like smooth muscles) operate automatically without conscious control.

5. **Conclusion**:
- Since smooth muscles cannot be controlled directly by our will, they are classified as involuntary muscles. Therefore, the correct answer to the question is "involuntary".

### Final Answer:
As functioning of smooth muscles can't be directly controlled, they are **involuntary**.

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