C is incorrect b/c it talks about mild & fleeting back pain at the time of injury, which the passage says nothing about

the passage DOES state that chronic back pain develops years after a herniated disk, but, that is technically irrelevant to what C is saying

I chose C as well lol

Hi! Yes, they are not explicitly provided. Assumptions in an argument are what's "implied" from the stated premise and the conclusion. A strong argument (the one on the far left of the spectrum) contains no assumptions. It is "bulletproof." Anything besides that has at least one assumption that you can try to identify.

It is not that we are thinking or making them up on our own. Rather, we are just thinking to identify what they are; they already exist.