PLEASE HELP ASAP WILL MARK Isolated bodies of water follow the theory of island biogeography. Two bodies of water that are approximately the same size, depth, and latitude are found to have a large difference in the number of species inhabiting them. What is the most influential contributing island biogeography factor resulting in the difference in the number of species found in each body of water?

Fewer predators in one body of water than the other
One body of water has a higher salinity than the other
One body of water is slightly warmer than the other
The relative ages of the two bodies of water differ greatly