Ecosystems change when
a.
living components of an ecosystem change
b.
nonliving components of an ecosystem change
c.
their stability is disrupted
d.
all of the above

I believe its D. all of the above because if living components change, then there will either be a surplus of food or more competition between organisms. Also if nonliving things change, then the ecosystem will change because for example if it were too cold then it could disrupt the ecosystem. And if their stability is disturbed, they can definitely change. Hope this helps. Feel free to ask more questions.