Question ID:PT67 S4 Q6 Passage:Columnist: Contrary to what many people believe, the number of species on Earth is probably not dwindling. Extinction is a natural process, and about as many species are likely to go extinct this year as went extinct in 1970. But the emergence of new species is also a natural process; there is no reason to doubt that new species are emerging at about the same rate as they have been for the last several centuries. Stem:Which one of the following, if true, most weakens the columnist's argument? Correct Answer Choice:AChoice A:In 1970 fewer new species emerged than went extinct. Choice B:The regions of the world where new species tend to emerge at the highest rate are also where species tend to go extinct at the highest rate. Choice C:The vast majority of the species that have ever existed are now extinct. Choice D:There is no more concern now about extinction of species than there was in 1970. Choice E:Scientists are now better able to identify species facing serious risk of extinction than they were in 1970.