Final answer:
The normal blood pressure reading from the options provided is (A) 119/75 mm Hg, which is below the threshold of 120/80 mm Hg set by heart health guidelines.
Step-by-step explanation:
The blood pressure reading that falls within the normal range is (A) 119/75 mm Hg. According to the guidelines from the American College of Cardiology and the American Heart Association, normal blood pressure is defined as less than 120/80 mm Hg. Blood pressure readings such as 135/90 mm Hg are considered as stage 1 hypertension, while readings like 140/80 mm Hg or higher fall into stage 2 hypertension. A reading of 91/70 mm Hg could be considered lower than normal but not necessarily hypotensive unless it causes symptoms.
Blood pressure measures the force exerted by circulating blood on the walls of blood vessels. It is usually measured using a sphygmomanometer and is reported as systolic pressure (the maximum pressure during one heartbeat) over diastolic pressure (the minimum pressure between two heartbeats). Systolic pressure is the first (higher) number, and diastolic pressure is the second (lower) number.