When an ecosystem changes, the results are __. a. all positive
b. all negative
c. neither positive nor negative
d. mixed between positive and negative

pls help

d). mixed between positive and negative.

Explanation:

The changes in an ecosystem bring both positive, as well as, negative consequences. On one hand, it promotes increased production of food that helped alleviate famines and poverty, enhanced resources' supply promoted economic growth and development, better assistance in dealing with climatic changes, etc. While on the other hand, the rapid changes in the ecosystem have led a number of species to migrate and many others to reach the verge of extinction. Some even have got extinct by now like dinosaurs. It has also led to a degradation of environmental resources and a reduction in biodiversity. Thus, it has both positive and negative impacts. Hence, option d is the correct answer.