Your premise diagrams look good, Sarah, so now link those two up through the common element of "investment", like this (and I am abbreviating the terms here):
Emerge 

 Invest 

 Confidence
The conclusion gives us a new conditional claim, that when you put collective goals first, you don't get that rapid emergence. The new term is not just "goals", but is "put(ting) collective goals before individual goals". Simplified, that looks like this:
Collective 
 Emerge
 Emerge
In order to justify (prove) that conclusion, we need Collective (that is, putting collective goals ahead of individual goals) to be sufficient for something that will get us to 
Emerge. We can do that through the contrapositive of the original chain, which would be:
Confidence  Invest
 Invest  Emerge
 Emerge
Answer D gets us there by making Collective sufficient for 
Confidence - from there, just follow the contrapositive chain all the way to 
Emerge and your conclusion is justified!
Collective 
 Confidence
Confidence  Invest
 Invest  Emerge
 Emerge
Answer C makes no such connection. So what if putting individual goals first and being willing to invest will lead to rapid emergence? How does that prove that putting collective goals first won't? What if people in countries that put collective goals first also have confidence and invest? If you want to justify a conclusion about putting collective goals first, you need to talk about putting collective goals first.
Nice job diagramming the premises! Just be sure to carry that through all the way to find what is missing from the diagram to link up the conclusion.
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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