One of the Graphs Below Shows the Rate of Flow $p(R(15))$

Multiple Choice

One of the graphs below shows the rate of flow, R, of blood from the heart in a man who bicycles for twenty minutes, starting at t = 0 minutes.The other graph shows the pressure, p, in the artery leading to a man's lungs as a function of the rate of flow of blood from the heart.Estimate $p(R(15) )$
.

A) 26.5
B) 23
C) 17.5
D) 13