Zeno argued you can never cross a room: first half the distance, then half the rest, forever. Why does the mathematics of series dissolve the paradox?

C. Because the times form a convergent series with a finite total

The steps shrink fast enough that the times sum to a finite number: infinitely many additions with a finite total. Zeno's error was assuming an infinite count of intervals means infinite duration, and the resolution had to wait about two thousand years for the definition of a convergent series.