Critical Reasoning

Ringtail opossums are an Australian wildlife species that is potentially endangered. A number of ringtail opossums that had been orphaned and subsequently raised in captivity were monitored after being returned to the wild. Seventy-five percent of these opossums were killed by foxes, a species not native to Australia. Conservationists concluded that the native ringtail opossum population was endangered not by a scarcity of food, as had been previously thought, but by non-native predator species against which the opossum had not developed natural defenses.
Which one of the following, if true, most strongly supports the conservationists' argument?
(A) There are fewer non-native predator species that prey on the ringtail opossum than there are native species that prey on the ringtail opossum.
(B) Foxes, which were introduced into Australia over 200 years ago, adapted to the Australian climate less successfully than did some other foreign species.
(C) The ringtail opossums that were raised in captivity were fed a diet similar to that which ringtail opossums typically eat in the wild.
(D) Few of the species that compete with the ringtail opossum for food sources are native to Australia.
(E) Ringtail opossums that grow to adulthood in the wild defend themselves against foxes no more successfully than do ringtail opossums raised in captivity.

Will post Official Answer in two days. Need experts opinion first.

DavidG@VeritasPrep wrote:

lheiannie07 wrote:Ringtail opossums are an Australian wildlife species that is potentially endangered. A number of ringtail opossums that had been orphaned and subsequently raised in captivity were monitored after being returned to the wild. Seventy-five percent of these opossums were killed by foxes, a species not native to Australia. Conservationists concluded that the native ringtail opossum population was endangered not by a scarcity of food, as had been previously thought, but by non-native predator species against which the opossum had not developed natural defenses.
Which one of the following, if true, most strongly supports the conservationists' argument?
(A) There are fewer non-native predator species that prey on the ringtail opossum than there are native species that prey on the ringtail opossum.
(B) Foxes, which were introduced into Australia over 200 years ago, adapted to the Australian climate less successfully than did some other foreign species.
(C) The ringtail opossums that were raised in captivity were fed a diet similar to that which ringtail opossums typically eat in the wild.
(D) Few of the species that compete with the ringtail opossum for food sources are native to Australia.
(E) Ringtail opossums that grow to adulthood in the wild defend themselves against foxes no more successfully than do ringtail opossums raised in captivity.

Will post Official Answer in two days. Need experts opinion first.

Conservationists' conclusion: ringtail opossums are endangered by non-native predator species the opossums haven't developed natural defenses against
Premise: 75% of opossums raised in captivity and returned to the wild were killed by foxes, which are not native to Australia.

Notice the language shift. The conclusion is about the opossums's endangerment in general , but the conclusion is about opossums raised in captivity and released. Therefore, the author has to assume that opossums raised in captivity are representative of the entire opossum population, and that wild opossums are no more adept at defending themselves than those raised in captivity. This is what E gives us,

Thanks a lot!