**Core Concept**
The question tests the understanding of blood pressure measurement techniques and the effects of adrenaline on blood pressure. **Blood pressure** is the force exerted by blood on the vessel walls, and its measurement can be affected by various factors, including the method of measurement.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's analyze the situation: Rakesh uses a mercury **sphygmomanometer**, which is a direct and accurate method of measuring blood pressure, while Arif uses a **pressure transducer** and pulse tracing, which can be more prone to errors due to calibration issues or signal processing. Adrenaline increases **heart rate** and **vascular resistance**, leading to increased blood pressure.

**Why Each Wrong Option is Incorrect**
**Option A:** Not provided, so we cannot assess its correctness.
**Option B:** Not provided, so we cannot assess its correctness.
**Option C:** Not provided, so we cannot assess its correctness.
**Option D:** Not provided, so we cannot assess its correctness.

**Clinical Pearl / High-Yield Fact**
When measuring blood pressure, it's essential to consider the method of measurement and potential sources of error. Adrenaline can cause significant increases in blood pressure due to its effects on the **sympathetic nervous system**.

**Correct Answer:** Not provided, however typically the difference could be due to the method of measurement or calibration issues, often related to the **pressure transducer**.