Find out the correct match from the following `:-`
(i) Larynx -sound box
(ii) Trachea - complete cartilagenous rings
(iii) Epiglottis -elastic cartilagenous flap
(iv) Alveoli - very thin, irregular walled, non-vascularised bag like structured
(v) Pleural fluid - reduces friction on the lung surface

Options

A. `(i),(ii),(iii),(iv),(v)`
B. `(i),(iii),(iv),(v)`
C. `(i),(iii),(v)`
D. `(i)` and `(v)`

Answer

To solve the question, we need to match each term with its correct description. Let's analyze each option step by step.

### Step-by-Step Solution:

1. **Larynx - Sound Box**
- The larynx is indeed known as the "sound box" because it is responsible for producing sound. It contains the vocal cords and is located just below the pharynx.
- **Conclusion**: This match is correct.

2. **Trachea - Complete Cartilaginous Rings**
- The trachea, or windpipe, does have cartilaginous rings, but they are not complete. They are C-shaped rings that are open at the back, allowing flexibility and space for the esophagus.
- **Conclusion**: This match is incorrect.

3. **Epiglottis - Elastic Cartilaginous Flap**
- The epiglottis is a flap of tissue that prevents food from entering the trachea during swallowing. It is made of elastic cartilage, allowing it to bend and cover the trachea when necessary.
- **Conclusion**: This match is correct.

4. **Alveoli - Very Thin, Irregular Walled, Non-Vascularized Bag-like Structures**
- Alveoli are indeed the sites of gas exchange in the lungs. They are thin-walled, sac-like structures that allow for efficient diffusion of gases. However, they are vascularized as they are surrounded by capillaries for gas exchange.
- **Conclusion**: This match is incorrect.

5. **Pleural Fluid - Reduces Friction on the Lung Surface**
- Pleural fluid is found in the pleural cavity and serves to reduce friction between the lungs and the chest wall during breathing.
- **Conclusion**: This match is correct.

### Summary of Matches:
- (i) Larynx - Sound Box: **Correct**
- (ii) Trachea - Complete Cartilaginous Rings: **Incorrect**
- (iii) Epiglottis - Elastic Cartilaginous Flap: **Correct**
- (iv) Alveoli - Very Thin, Irregular Walled, Non-Vascularized Bag-like Structures: **Incorrect**
- (v) Pleural Fluid - Reduces Friction on the Lung Surface: **Correct**

### Final Answer:
The correct matches are:
- Larynx - Sound Box
- Epiglottis - Elastic Cartilaginous Flap
- Pleural Fluid - Reduces Friction on the Lung Surface