In investigating the microcirculation of the frog foot, you note the following about blood flow: .

A) blood flows smoothly through arterioles, capillaries, and venules at the same velocity
B) blood flow in the arterioles and venules is slow and smooth; it is very slow in the capillaries
C) blood flow in the arterioles is rapid and pulsating; it is very slow in the capillaries, and slow and smooth in the venules
D) blood flow in the arterioles and venules is rapid and pulsating; it is slow in the capillaries