isnt if a indicator word for sufficient then why are we putting in the sentence for negate necessary

For this, you have to understand necessity and sufficiency. Necessity means something is required for something else to happen. For example: “Alex gets a speeding ticket only if he speeds.”

So, the conclusion “Alex got a ticket, therefore he was speeding” is correct, because getting a ticket depends on him speeding. But speeding does not depend on whether he gets a ticket.

That’s why the conclusion “Alex was speeding, therefore he got a ticket” is incorrect just because he was speeding doesn’t mean he actually got caught and ticketed. In short, getting a ticket means he was speeding, but speeding doesn’t automatically mean he got a ticket. For something to be sufficient, it means it guarantees the result. For example: “If Alex speeds, then he will get a ticket.” That’s different from “only if,” because “if” makes speeding enough to cause the ticket, while “only if” just makes speeding required for a ticket.

@iselachavezg Hi! Yes that would be amazing!

Yeah I would love to join as well

I’m confused because I am viewing the first sentence as context because it is stating what the environmentalist perspective is, not the authors. So when the question is asking “Which one of the following most accurately expresses the environmentalist's main conclusion?” I am trying to find the answer using this sentence. “The complex ecosystem of the North American prairie has largely been destroyed to produce cattle feed” because after this sentence the author uses the indicator word ‘but’ to signal a shift into his own perspective. Like now I don't know what to tell from the main conclusion which would be the author's statement or solely the environmentalist conclusion.

@kaleighh.04 hey girl im also taking the lsat in April!