Answer: the correct option is D
Explanation:
The zoologist is recording the loss of wolves in her state and she recorded that the number of wolves, w, in the state on January 1.
One year later, there were 84 wolves in the state which is 23 fewer than the number of wolves in the state a year earlier. This means that a year later, the number of wolves was 23 fewer than w
The number of wolves in the state on January 1 would be the sum of the number of wolves in the state a year later and the number by which it became fewer than the number on January 1. This becomes
w = 84 + 23
w - 23 = 84