I think this is definitely WHO because the story is talking about a certain unknown character.
Well for reading the passage I will say the answer is (A).
Answer:
At the end of paragraph 1, when the author says “First, we must develop many different ways of putting the waste from these nuclear and chemical substances in, on, and around the earth” it helps shape the reader's perception of the text as by starting to go into more details and more ideas on poisoning the Earth.
