C

Hello @tomgbean, Good question. The answer is that we do not need to know that it is less harmful. I believe that C is mostly meant to point out that Tina is using old information. It rejects her claim that paper cup production uses more petroleum than foam cup production. It doesn't refute all of her claims, but it effectively refutes one. Tina might fire back and say that wastewood is also harmful, but still Mark has successfully countered one of her arguments for now. It might not be a perfect counter, but the rest of the answer choices are pretty easy to eliminate. They all directly oppose his point that paper cups are less harmful.

I think there is a typo in the answer choice of this question. What exactly are petroleum occasions? I also think it doesn't make sense grammatically

@Zara The word "occasions" is actually being used correctly. The formal use of the word occasion is defined as "cause (something)" So if we look back at the sentence used in answer C and replace the word "occasions" with "cause" it looks like, "The production and transportation of petroleum CAUSES serious environmental pollution" Hopefully this shows why there is no typo!