What constitutes a normal adult blood pressure range?

• A. Systolic 120–140 mmHg and Diastolic 80–90 mmHg
• B. 100-140 systolic, 70-90 diastolic
• C. 80-100 systolic, 50-70 diastolic
• D. Systolic 90–120 mmHg and Diastolic 60–80 mmHg

Answer: (D)

Blood pressure has two readings: the pressure in the arteries when the heart contracts and the pressure when the heart relaxes. A normal adult range is a middle zone for both numbers—neither too high nor too low. When both readings stay within this middle zone, organs receive adequate blood flow without unnecessary strain on the vessels. If the readings trend higher, especially the top value or the bottom value, that indicates elevated blood pressure over time. If the bottom value drops too low, circulation can be impaired. The best choice describes both numbers staying in that normal middle zone, while the other options show values that are too high or too low.