What is "change" when we are talking about natural and physical systems?
a.
repeated processes that are used in a variety of ways
b.
information that has been proven to be true
c.
a process for using knowledge and skills to acquire new knowledge
d.
a variable or alteration to one part that affects an entire system

D

Explanation:

A variable or alteration to one part that affects an entire system

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.