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 those 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: Ringtail opossums that grow to adulthood in the wild defend themselves against foxes no more successfully than do ringtail opossums raised in captivity.
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: There are fewer non-native predator species that prey on the ringtail opossum than there are native species that prey on the ringtail opossum.
Choose A, B, C or D as your solution.
A