Critical Reasoning (CR) | Re: When exercising the muscles in one’s back, it is important

Can anyone please explain to me why option C is incorrect? When I negated the to option, it seemed to weaken the conclusion.

I am happy to help

The problem with this statement is the word "generally". This means that sometimes one will have a healthy back and sometimes one will not have a healthy back.

This is not necessary for the argument to hold.

Also, if you negate