Answer:
C. Large, deep body of water that contains fresh water
Step-by-step explanation:
Keywords in question: "Freshwater wetland"
Answer A does not have those keywords in the answer. It does not talk about water, it talks about acidic areas!
Answer B does talk about water, but it's not specifically saying anything about freshwater. It talks more about the landscape of the area feeding water into rivers.
Answer C says fresh water at the end of the answer. It's telling you that the body of water contains fresh water. So, this phrase does describe the qualities of fresh water wetland.
Hope this helps you! :3