Blood pressure is measured by

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Pressure Measurement**: Blood pressure is the force exerted by circulating blood on the walls of blood vessels. It is typically measured in millimeters of mercury (mmHg) and consists of two values: systolic and diastolic pressure.

2. **Identifying the Correct Instrument**: Among the given options, we need to identify which instrument is specifically designed to measure blood pressure. The options provided are:
- Sphygmomanometer
- Phonocardiogram
- Electrocardiogram
- Stethoscope

3. **Analyzing Each Option**:
- **Sphygmomanometer**: This is the correct instrument used to measure blood pressure. It provides readings for both systolic (the upper number, typically around 120 mmHg) and diastolic (the lower number, typically around 80 mmHg) pressures.
- **Phonocardiogram**: This instrument detects heart sounds, particularly any abnormal sounds like murmurs, but it does not measure blood pressure.
- **Electrocardiogram (ECG)**: This is a graphical representation of the electrical activity of the heart, showing depolarization and repolarization of the heart chambers, but it does not measure blood pressure.
- **Stethoscope**: While a stethoscope is used to listen to heart sounds and breathing, it does not measure blood pressure directly.

4. **Conclusion**: After evaluating all the options, the only instrument that measures blood pressure is the **sphygmomanometer**.

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

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