If you need to drive a total of 448.6 miles and you are volunteering to drive the first 14 miles, you will be driving 14 miles.
However, if you're looking for how much distance is remaining after your segment of the trip, you can calculate that by subtracting the distance you will drive from the total distance:
448.6 miles - 14 miles = 434.6 miles remaining.
But based on your question, the answer is simply 14 miles that you will be driving. If your question was about the total distance left or something else, please clarify.
In the context of the options you provided, it seems there was a misunderstanding as none of the options correctly reflect the distance you will drive.