Question

read the paragraph. then answer the question.
people can change ecosystems too. over time, people have moved plants and animals from their native ecosystems to new ones. sometimes this changes the food chain of the ecosystem or takes space away from native plants and animals.
which statement is the best inference for the paragraph?
a. people are the only ones who should change ecosystems.
b. change in an ecosystem might be positive or negative.
c. people should never change ecosystems in any way at all.
d. plants and animals are in their native ecosystems.

Explanation:

The paragraph states that people change ecosystems (by moving plants/animals). It also mentions that changes can affect the food chain (implying changes have an impact - positive or negative). Option A is wrong as it says people are the only ones (the text doesn't imply that). Option C is wrong as it says people should never change (the text just states they do change). Option D is wrong as the text says plants/animals are moved from native ecosystems (not that they are in their native ones in the context of being moved). Option B aligns with the idea that changes (which people cause) can have an impact (positive or negative) on the ecosystem (like affecting the food chain etc.).

Answer:

B. Change in an ecosystem might be positive or negative.