11.) Is the letter choice "A.)".
An ecosystem can be described as a community of animals, plants and bacteria that interact with one another.
This can be proved in paragraph 2;
"Ecosystems also can be thought of as the interactions among all organisms in a given habitat."
12.) Is the letter choice "C.)"
Land development.
This can be proven in paragraph 2;
"Human activities can harm or destroy local ecosystems unless actions such as land development for housing or businesses are caredully planned to conserve and sustain the ecology of the area."
13.) Is the answer choice "A."
Protecting ecosystems.
This is proven (given) in paragraph 2 by summary;
"An important part of ecosystem management involves finding ways to protect and enhance economic and social well-being while protecting the physical environment."
I hope this helps!
I need more details to answer this question
