The answer is simply: A the other person is too confusing...
Answer:
Diatoms!!
Explanation:
B. Parasitism
C. Predation
D. Competition
(I know that B is wrong)
B. animal training
C. modeling
D. observing
animal training is not a basic method used by ecologists to study the living world.
The practice of teaching animals particular behaviors to particular circumstances or stimuli is known as animal training. Training may be done for friendship, detection, protection, or enjoyment, among other things.
Depending on the training technique employed and the goal for which the animal is being trained, several types of training are given to animals. A seeing-eye dog, for instance, will be trained to accomplish a different objective than a wild animal in a circus.
There are organizations that certify animal trainers in different nations. They don't have any common objectives or specifications, and they don't stop someone from using the title or working with animals.
Therefore, animal training is not a basic method used by ecologists to study the living world.
To learn more about Animal training, refer to the link:
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