What is the normal diastolic blood pressure in a normal healthy adult human ?

80 mm Hg

The correct answer is Option (3) - 80 mm Hg

Blood pressure is the pressure against the walls of the blood vessels produced by the discharge of blood into them by contraction of the left ventricle.

Systolic pressure: The temporary rise in BP during the contraction of the heart is called systolic pressure.

Diastolic pressure: The temporary fall in BP during the relaxation of the heart is termed as diastolic pressure.

For a healthy resting adult person, the average systolic/ diastolic pressures are 120/80 mm Hg in arteries near the heart.