Explain giving reasons. 'The presence of CO reduces the amount of haemoglobin available in the blood for carrying oxygen to the body cells'.

Explanation

### Step-by-Step Solution:

1. **Understanding Hemoglobin's Function**: Hemoglobin (Hb) is a protein found in red blood cells that is responsible for transporting oxygen from the lungs to the body’s tissues and returning carbon dioxide from the tissues back to the lungs.

**Hint**: Recall the primary role of hemoglobin in oxygen transport.

2. **Introduction to Carbon Monoxide (CO)**: Carbon monoxide is a colorless, odorless gas that is produced during the incomplete combustion of carbon-containing fuels. It is particularly prevalent in automobile exhaust.

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