Explain

Alright so let's breakdown this argument: Conclusion: when you choose HomeGlo Exterior Enamel, you will know that you have chosen the most environmentally safe brand of paint manufactured in this county today. Why? HomeGlo recently won the prestigious Golden Paintbrush Award, which is given to the paint manufacturer who has increased the environmental safety of its product most over the past three years. So what's the flaw here? Well, just because HomeGlo has improved the most, that doesn't mean it is the best. What if three years ago HomeGlo had a rating of 1/10 and they were able to raise up to 7/10? Well, there could still be companies with ratings of 8/10 or 9/10. In that situation, regardless of HomeGlo's improvement, it doesn't make it the best. Answer choice (D) has similar flawed reasoning. Conclusion: if Jerrold and his classmates are ranked according to their current academic performance, Jerrold must hold the highest ranking. Why? Jerrold's teachers recognized him as the student who has shown the most academic improvement. Again, we have the same issue. Just because Jerrold showed the most improvement, that doesn't mean he has the highest ranking. He could have raised his grade from an F to a B. But other students could have straight A's. Thus, having the most improvement does not mean you are the best, just as in the argument. Therefore, answer choice (D) is the correct answer. If you have any specific questions about the other answer choices, please feel free to clarify. Hope that helped! Please let us know if you have any other questions.

Why not A?

I second that^. I was pretty torn between D and A. Would you mind explaining why A is incorrect? Thank you!