Why do fighter jets land faster than Jumbo commercial aircraft? From my own understanding, the bigger (and heavier) aircraft, the higher approach speed it needs to keep itself from stalling. According to this site, the approach speed of an A380 is 140 knots, and 160 knots for a 747. In contrast, the F-16's landing speed is 141 knots, and 135 knots for the F-35C.

Doing mass-to-speed ratio, it doesn't make any sense to me. Could you explain why do fighter jets land faster while they are lighter than large commercial aircraft?
It is not only the mass that affects the landing speed. Wing area plays an important role as well. 

A larger wing can lift more weight at the same speed than a smaller wing. If you compare the wing loading of these aircraft the differences are smaller:

A388:


Maximum landing weight: 391000 kg
Wing area: 845 m2
Wing loading: 463 kg/m2


B744:


Maximum landing weight: 295000 kg
Wing area: 525 m2
Wing loading: 468 kg/m2


F-16A:


Estimated landing weight: 13000 kg
Wing area: 28 m2
Wing loading: 464 kg/m2