单项选择题
Previously, the sack-like rabbit appendix was thought to serve primarily as a reservoir for the bacteria involved in hindgut fermentation, a explanation that failed to account for the absence of an appendix in other animals with similar digestive systems or for its presence in humans. Microscopic research revealed that the appendix contains a significant amount of lymphoid tissue, similar aggregates of which tissue occur in other areas of the gastrointestinal tract. These are involved, possibly, in the body’’s ability to recognize foreign antigens in ingested material, but the evidence is inconclusive, to the extent that scientists have long discounted the human appendix as a "vestigial" organ. However, a growing body of evidence suggests that the appendix, far from being a "vestigial organ", hag a significant function as a part of the body’s immune system. The appendix achieves its greatest development shortly after birth, when immune response is first developing, then regresses with age, when the immune response mediated by the appendix may relate to such inflammatory conditions as ulcerative colitis, which in adults necessitates the organ’s surgical removal.
Which of the following best describes the relationship of the second paragraph to the first（） A．The second paragraph relies on different evidence in drawing a conclusion similar to that expressed in the first paragraph.
B．The second paragraph provides further elaboration on why an assertion made at the end of the first paragraph proves true in most cases.
C．The second paragraph provides additional information in support of a hypothesis stated in the first paragraph.
D．The second paragraph provides an example of a case in which the assumption described in the first paragraph is unwarranted.
E．The second paragraph describes a phenomenon that has the same cause as the phenomenon described in the first paragraph.