Which of the following instrument is used to measure blood pressure?

Sphygmomanometer.

The correct answer is Option (3) –Sphygmomanometer.

Blood pressure is measured with an instrument called sphygmomanometer. High blood pressure is also called hypertension and is caused by the constriction of arterioles, which results in increased resistance to blood flow. It can lead to the rupture of an artery and internal bleeding.