Answer:
C
Explanation:
I hope this is correct and have a great day
Frequency = speed of light
---------------------------
wavelength
= 3 x 10^8
------------------------
344 x 10^-9
= 8.72 x 10^14 Hz.
Hope this helps!
There's a lot of capillaries in the lungs because the blood needs to be transferred and the capillaries are the smallest vessels that can do this.