Residence time of Carbon monoxide is

Options

A. 65 days
B. 2 to 4 years
C. 4 days
D. 3 days

Answer

To determine the residence time of carbon monoxide (CO), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Residence Time**:
- Residence time refers to the average time a substance stays in a particular system or environment before being removed or transformed. In this case, we are looking at carbon monoxide in the human body.

2. **Identify the Substance**:
- The substance in question is carbon monoxide (CO), which is a colorless, odorless gas that is harmful to humans. It can interfere with the body's ability to transport oxygen.

3. **Research the Residence Time of Carbon Monoxide**:
- The residence time of carbon monoxide in the human body is a factual value that can be found in scientific literature.

4. **State the Residence Time**:
- Based on the information available, the residence time of carbon monoxide in the human body is approximately **65 days**.

5. **Conclude the Answer**:
- Therefore, the answer to the question regarding the residence time of carbon monoxide is **65 days**.