Why D instead of C?

Hi @Vennela-Vellanki, Thanks for the question! So we’re being asked here what the author would agree with in regards to standards of living. Think about the main idea of the passage. The whole point is that industrial ecosystems can let there be more people and maintain the standard of living, and that overly depleting natural resources can be avoided. That’s exactly what (D) says. (C), on the other hand, says the opposite. It says that the standard of living CANNOT be sustained of the population increases. The author is saying that it can. Hope this helps! Feel free to ask any other questions that you might have.

E seems like a pretty good answer choice too. I see support for it at the end of P1.

I think that the end of the first paragraph does give support to the idea that resources might be depleted unless something is done, it doesn't directly support the idea that we need to reduce standards of living, in fact, the paragraph explicitly offers an alternative, to find substitutes.