Let’s say we want to find the size of a deer population. Suppose that we capture 80 deer, tag them, and release them back into the forest. After some time has passed—allowing the marked deer to thoroughly mix with the rest of the population—we come back and capture another 100 deer. Out of these deer, we find that 20 are already marked. Using this information, what can you estimate the deer population to be?

A. 1,000
B. 400
C. 200
D. 800
E. 600