单选题 . ①Was resource intensification—an increase in labor and time devoted to subsistence activities in order to increase food yields—by Dorset Paleo-Eskimos and Recent Indians on the island of Newfoundland simply a response to population pressure? ②Not exactly. ③On Newfoundland, population pressure did not result from a steadily growing resident population but, rather, from the arrival and lingering presence of new and significantly different populations. ④Newfoundland's hunter-gatherer populations—both resident and newcomer—adjusted to the presence of other populations through niche differentiation. ⑤Building on a tradition that emphasized marine resources, Dorset Paleo-Eskimos intensified their harvest of seals in response to the arrival of Recent Indians in the first few centuries A.D. ⑥Recent Indians who were more familiar with broad-based, interior-maritime adaptation, intensified this strategy to cope with the Dorset.41. According to the passage, which of the following resulted from the arrival of the Recent Indians? ______

A、 The Dorset Paleo-Eskimos were forced to compete with the Recent Indians for a limited supply of seals.
B、 The Dorset Paleo-Eskimos spent more time harvesting seals than they had in the past.
C、 The Dorset Paleo-Eskimos increased the amount of labor and time devoted to defending their territory.
D、 The Dorset Paleo-Eskimos began to adopt new subsistence strategies they learned from the Recent Indians.
E、 The previously steady growth of the Dorset Paleo-Eskimos population came to a halt.

【正确答案】 B

【答案解析】 B：根据题干，本题答案定位到第⑤句，即为了应对美国原住民的到来，古阿拉斯加州原住民会进行资源强化，因此选项B正确。
A：古阿拉斯加州原住民为了应对美国原住民会更多地捕杀海豹，但是未必会和美国原住民竞争。
C：文中未提及defending their territory。
D：文中未提及learned from the Recent Indians。
E：文中未提及population came to a halt。