Can you explain why C is incorrect?

Hi @odsimkins, Thanks for the question! So (C) tells us that the second study included about 15% more individual plants than the first study did; in other words, it just tells us that the second study had a higher absolute number of plants. But the total number of plants being measured shouldn’t have an effect on the proportion of plants that have patterned stems, since there’s no reason to assume that the 15% of plants added would have been unrepresentative of the sample as a whole. So adding another representative sample would keep the proportions the same and wouldn’t explain anything, which is why (C) isn’t correct. Hope this helps! Feel free to ask any other questions that you might have.