Blood pressure is measured by:-

Options

A. Sphygmomanometer
B. Phonocardiogram
C. Electrocardiogram
D. Stethoscope

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Pressure:**
- Blood pressure is defined as the force exerted by circulating blood on the walls of blood vessels, particularly arteries.

2. **Identifying the Measurement Instrument:**
- To measure blood pressure, we need to identify the correct instrument from the given options: sphygmomanometer, phonocardiogram, electrocardiogram, and stethoscope.

3. **Evaluating the Options:**
- **Sphygmomanometer:** This is the correct instrument used to measure blood pressure. It consists of an inflatable rubber cuff, a column of mercury (or aneroid gauge), and a graduated scale to read the pressure.
- **Phonocardiogram:** This instrument records the sounds made by the heart, not blood pressure.
- **Electrocardiogram (ECG):** This is used to evaluate the heart's electrical activity and rhythm, not for measuring blood pressure.
- **Stethoscope:** This device is used to listen to internal sounds of the body, such as heartbeats and lung sounds, but it does not measure blood pressure.

4. **Conclusion:**
- Based on the evaluation, the correct answer is that blood pressure is measured by a **sphygmomanometer**.

**Final Answer:**
Blood pressure is measured by a sphygmomanometer.

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