This is a weaken question. You have two speakers, each of whom presents an argument and support for their position. The question stem then asks you to help one of the speakers (Mark) weaken the other speaker's (Tina's) argument.
So, let's first examine Tina's argument carefully.
Tina's conclusion is that paper cups are "a worse choice" (than plastic-foam cups) for the environment. Her premises in support of this claim are:
1. Making paper to produce paper cups burned more petroleum than was used for foam cups
2. Making paper to produce paper cups uses 12x as much steam
3. Making paper to produce paper cups uses 36x as much electricity
4. Making paper for paper cups uses 2x as much cooling water
5. Because paper cups are heavier, their transportation takes more energy
6. Paper mills produce water pollution, and
7. When paper cups decay they produce methane, a gas that contributes to harmful global warming.
Whew! Lots of support for her position; Tina is not the kind of person who makes unsupported claims!
Now our task is to help poor Mark counter one or more of the pieces of evidence Tina has offered in support of her conclusion.
Answer choice (C) does exactly this. How? It states that "the energy that runs paper mills now comes from burning waste wood rather than petroleum." This statement would counter item #1 of Tina's argument.
Hope this helps! Please let us know if you have any additional questions.
