The primary purpose of the passage is to
A. present evidence that several phocid species use the maternal fasting strategyB. explain why the maternal strategy typically used by phocids is different from thematernal strategy used by otariidsC. argue that zoologists 'current understanding of harbor seals' maternal strategy isincorrectD. describe an unexpected behavior observed in harbor seals and propose anexplanation that may account for that behaviorE. describe evidence concerning the maternal strategy of the harbor seal and suggestthat the harbor seal belongs to the otariid rather than to the phocid family

The answer is D because the first paragraph of the passage contains a "however" in the middle. This clearly depicts that the author is making an effort to show a different view other than the normal thinking. Furthermore, in the second paragraph of the passage, the author is simply trying to explain the reasons why seals are different and the need for them to forage.

Answer Link