GMAT Critical Reasoning (CR) | Re: In Wareland last year, 16 percent of licensed drivers under 21 and 11

I am still struggling to eliminate C although I don't have a problem with C.

Conclusion:
Greater Experience + Caution = Safe drivers (for 65+ age group)

Now option C talks about Caution in age 65+ drivers. Why it can't be an assumption?
Is it, on the other hand, fair to say that: C is an inference from the argument?

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