GMAT Critical Reasoning (CR) | Does the sentence play any role in the argument?

Does the sentence ("it takes several pounds of grain to produce one pound of meat") play any role in the argument? i want to mean that if i remove this part from the argument, will it hamper the correct answer option E? Actually, I'm not removing anything from the original question; I'm just doing that to convince myself that I've understood the question or not.

also, in answer option E, the word "radically" means what? Could you explain it, please?
Thanks...

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