I think B is the correct answer. Answer choices C & D are about dolphins, but they do not have anything related to negative effects surrounding human and dolphin interaction. A, on the other hand, may seem like a good choice, but then again, the answer is too vague.
Answer:
Enzymes help speed up chemical reactions in the human body. They bind to molecules and alter them in specific ways. They are essential for respiration, digesting food, muscle and nerve function, among thousands of other roles.
Explanation:
Also the alimentary canal or digestive tract
Sustainability refers to how a system remains biodiverse and productive over long periods of time. Succession is a series of predictable changes that occur in a community over time. After a fire, volcano, or other disaster, succession enables an ecosystem to recover.