PTA.S4.Q16 - Scientists recently discovered that...

juliapellicane

I answered C for this question, when the answer was B, but I'd like further review on this answer.

Admin Note: Edited title. Please use the format: "PT#.S#.Q# - brief description of the question."

maco4538

MSS question require you to recognize the subtle but essential difference between what could be true and what must be true. Afterall, if it could be true then it could also be false. The right answer must be true.

Look at C: Carcinogenic chemicals usually cause some immediate cell death, even in small doses.

At best this could be true, but based on the information in the passage we can't say for certain that this must be true. The passage only provides information on the effects of "massive" doses, so we don't know the effects of small or even moderate doses.

Look at B: studies have overestimated the degree in which an additive was carcinogenic.

The passage tells us that the study rates the degree in which an additive was carcinogenic in proportion to the amount of cell death that occurs when a massive (more than necessary) dose of the additive is administered.