Which one of the following organs in the human body is most affected due to shortage of oxygen?

Options

A. intestine
B. skin
C. kidney
D. Brain

Explanation

To solve the question of which organ in the human body is most affected by a shortage of oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Importance of Oxygen**: Recognize that oxygen is crucial for cellular respiration, which is the process by which cells produce energy. This energy is essential for various metabolic activities in the body.

2. **Evaluate the Options**: The options given are:
- Intestine
- Skin
- Kidney
- Brain

3. **Analyze Each Organ**:
- **Intestine**: While it requires oxygen, it has a good blood supply and can function for a short time without it.
- **Skin**: The skin can survive without a constant supply of oxygen for a limited time due to its ability to utilize anaerobic processes.
- **Kidney**: The kidneys also have a rich blood supply and can tolerate short periods without oxygen.
- **Brain**: The brain is highly sensitive to oxygen levels. It requires a continuous supply of oxygen to function properly and cannot survive without it for more than a few minutes.

4. **Conclude the Most Affected Organ**: Based on the analysis, the brain is the organ that is most affected by a shortage of oxygen. It cannot survive without oxygen even for a few seconds.

5. **Select the Correct Answer**: Therefore, the correct answer to the question is option number 4, the brain.

### Final Answer:
The organ in the human body that is most affected due to a shortage of oxygen is the **brain**.

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