我看了这题的解释可是还是不太明白，这里第一段不是提出旧观点，然后提出新观点吗？那这样C答案岂不是更好？为什么C不对？

26. The main topic of the passage is

(A) the early development of embryos of lower marine organisms

(B) the main contribution of modern embryology to molecular biology

(C) the role of molecular biology in disproving older theories of embryonic development

(D) cell determination as an issue in the study of embryonic development

(E) scientific dogma as a factor in the recent debate over the value of molecular biology

26.

D is the best answer. In identifying the main topic of the passage, you must consider the passage

as a whole.

· In the first paragraph, the author provides a historical context for the debate described.

· In the second paragraph, concerning when and how the determination of embryo cells takes place.

· The third and forth paragraphs provide a specific example of the “Recent discoveries in molecular biology” (lines 28-29) that may lead to the resolution of that debate.