In which of the following cartilaginous ring support will not be observed?

Options

A. Secondary bronchi
B. Trachea
C. Initial bronchioles
D. Respiratory bronchioles

Answer

To solve the question regarding which cartilaginous ring support will not be observed, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Respiratory System**:
- The respiratory system includes structures such as the trachea, bronchi, and bronchioles. The trachea is supported by cartilaginous rings, which help maintain its structure and keep it open for air passage.

2. **Identify the Function of Cartilaginous Rings**:
- Cartilaginous rings are made of cartilage and provide structural support to the airways. They prevent the collapse of these structures during breathing.

3. **Examine the Options Provided**:
- **Option 1: Secondary Bronchi** - The secondary bronchi do have cartilaginous support.
- **Option 2: Trachea** - The trachea is well-known for its cartilaginous rings.
- **Option 3: Initial Bronchioles** - Initial bronchioles still have some cartilaginous support.
- **Option 4: Respiratory Bronchioles** - These are the smallest airways and do not have cartilaginous rings.

4. **Determine the Correct Answer**:
- Since the respiratory bronchioles do not have cartilaginous rings, the correct answer to the question is **Option 4: Respiratory Bronchioles**.

### Final Answer:
The cartilaginous ring support will not be observed in **Respiratory Bronchioles**.

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