Why is E not correct?

Hi, this is a very tough question. I think the main issue with E is that we don't know anything really about local as opposed to regional competition. I think the author would agree that the advantage of the rate of speciation hypothesis is that it considers how species form on a regional level, and the author criticizes another theory on the ground that looking only at local ecology is not sufficient, but I don't think that we know enough about what it means to say local or regional competition.