The biotic elements of an ecosystem include: a. rocks and other non-living parts of a habitat. b. disturbances, such as forest fires. c. plants, such as trees and flowers. d. All of these choices are correct.

the answer is C

Explanation:

C is the only option that has living things. The definition of biotic is: relating to or resultion from living organisms.  Therefore, the only correct option would be the option pertaining to living things.

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