The right answer is D.
The density of a given population is calculated by dividing the number of inhabitants by the area expressed in km² (or in hectares).
Number of inhabitants ÷ area (in km²) = number of inhabitants / km²
A = 125000 organism/ 2.5 m2 = 50,000 organisms / m2
B = 13000 organisms / m2
C = 37500 organisms / m2
D = 200000 organisms / m2
I'm guessing its so they can be able to diagnose a patient and see whether they need treatment or not
Variation is the right answer hope this helps
