Instrument used to measure RBC count is :

Options

A. Haemometer
B. Electrocardiograph
C. Sphygmomanometer
D. Haemocytometer

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the instrument used to measure the RBC (Red Blood Cell) count.

2. **Analyzing Options**: We need to evaluate the different instruments mentioned in the context of their functions:
- **Hemometer**: This device measures hemoglobin concentration, not RBC count.
- **Electrocardiograph (ECG)**: This instrument records electrical signals from the heart, which is unrelated to RBC count.
- **Sphygmomanometer**: This device measures blood pressure, which is also not related to RBC count.

3. **Identifying the Correct Instrument**: The correct instrument for measuring RBC count is the **Hemocytometer**.
- A hemocytometer is a specialized microscope slide that contains a chamber designed to hold a specific volume of diluted blood.
- It allows for the manual counting of blood cells, including red blood cells, white blood cells, and platelets.

4. **Understanding the Terminology**: The term "hemocytometer" can be broken down:
- "Hemo" means blood.
- "Cyto" means cell.
- Therefore, a hemocytometer is a device that measures blood cells.

5. **Conclusion**: Based on the analysis, the instrument used to measure RBC count is the **Hemocytometer**.

**Final Answer**: Hemocytometer

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