Answer:
Their economic value -how much people would be willing to pay for them- is not revealed in market prices. ... The only option for assigning monetary values to them is to rely on non-market valuation methods.
Explanation:

The major reason for bird species decline is loss of habitat, especially grasslands and forests. All have experienced declines in some areas since the 1960s and '70s, and further declines are anticipated, due to habitat loss and deforestation, and climate change

Some of these animals habitats overlap with areas that humans count on for their livelihoods.
Answer:
I highly believe that the answer you're looking for is B.
Explanation: