Of all the mutations, we can conclude that one mutation would MOST LIKELY contribute to a rapid rate of extinction. That is

D) fused hands, no range of motion.

Explanation:

As we've seen in blind people, blindness is adapted to and other skills are highly developed to accommodate. B would be awkward, but not deadly. C would be fine mostly, since we are still able to see. However, D, with no range of motion, we would find it very difficult to defend ourselves and care for ourselves.

A) blindness

Explanation:

moving ball hits still ball. mover stops, hit ball moves. momentum transfer.