Rh factor is concerned with blood grouping. It derives its name from-

Options

A. Man
B. Chimpanzee
C. Monkey
D. Rat

Answer

### Step-by-Step Solution:

1. **Understanding the Rh Factor**: The Rh factor is a protein that can be present on the surface of red blood cells. It is a significant component in blood grouping.

2. **Origin of the Name**: The term "Rh" comes from the Rhesus monkey, a species used in early research to identify this blood group factor.

3. **Significance of Rh Factor**: The presence of the Rh factor in blood means that the blood type is Rh positive (e.g., A+, B+, AB+, O+). Conversely, if the Rh factor is absent, the blood type is Rh negative (e.g., A-, B-, AB-, O-).

4. **Conclusion**: Therefore, the Rh factor derives its name from the Rhesus monkey.

### Final Answer:
The Rh factor derives its name from the Rhesus monkey.

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