Hypoxia is the condition in which less oxygen becomes available to the tissure this may be due to

Options

A. lesser oxygen in the atomosphere
B. blockage in air passage
C. less rbcs in blood
D. all of the above

Answer

### Step-by-Step Solution:

1. **Understanding Hypoxia**:
- Hypoxia is defined as a condition where there is a deficiency of oxygen in the tissues. This can occur when the body or specific tissues do not receive enough oxygen.

2. **Types of Hypoxia**:
- Hypoxia can be classified into two types:
- **Generalized Hypoxia**: Affects the entire body.
- **Localized Hypoxia**: Affects specific organs or tissues.

3. **Causes of Hypoxia**:
- There are several factors that can lead to hypoxia:
- **Lesser Oxygen in the Atmosphere**: In environments where the concentration of oxygen is low (e.g., high altitudes, certain caves), the body may not receive enough oxygen.
- **Blockage in Air Passage**: Even if oxygen is available in the environment, any obstruction in the airways (like in cases of asthma or choking) can prevent oxygen from reaching the lungs.
- **Less RBCs in Blood**: Red blood cells (RBCs) carry hemoglobin, which is essential for transporting oxygen throughout the body. A low RBC count means less hemoglobin is available to carry oxygen, leading to hypoxia.

4. **Conclusion**:
- Since all the mentioned factors can contribute to hypoxia, the correct answer to the question is **"all of the above"**.

### Final Answer:
- **All of the above** (less oxygen in the atmosphere, blockage in air passage, less RBCs in blood).

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