gwd5-16关于选项的分析疑问？

Historian:  Newton developed mathematical concepts and techniques that are fundamental to modern calculus.  Leibniz developed closely analogous concepts and techniques.  It has traditionally been thought that these discoveries were independent.  Researchers have, however, recently discovered notes of Leibniz’ that discuss one of Newton’s books on mathematics.  Several scholars have argued that since the book includes a presentation of Newton’s calculus concepts and techniques, and since the notes were written before Leibniz’ own development of calculus concepts and techniques, it is virtually certain that the traditional view is false.  A more cautious conclusion than this is called for, however.  Leibniz’ notes are limited to early sections of Newton’s book, sections that precede the ones in which Newton’s calculus concepts and techniques are presented.

In the historian’s reasoning, the two boldfaced portions play which of the following roles?

1. The first provides evidence in support of the overall position that the historian defends; the second is evidence that has been used to support an opposing position.
2. The first provides evidence in support of the overall position that the historian defends; the second is that position.
3. The first provides evidence in support of an intermediate conclusion that is drawn to provide support for the overall position that the historian defends; the second provides evidence against that intermediate conclusion.
4. The first is evidence that has been used to support a conclusion that the historian criticizes; the second is evidence offered in support of the historian’s own position.
5. The first is evidence that has been used to support a conclusion that the historian criticizes; the second is further information that substantiates that evidence.

文章我明白，但是答案D 的The first is evidence that has been used to support a conclusion that the historian criticizes我的理解是the first 是用来作为historian反对的观点的证据，那就是传统观点的证据喽？那岂不是错了？请教

Historian:  Newton developed mathematical concepts and techniques that are fundamental to modern calculus.  Leibniz developed closely analogous concepts and techniques.  It has traditionally been thought that these discoveries were independent.  Researchers have, however第一个转折, recently discovered notes of Leibniz’ that discuss one of Newton’s books on mathematics.  Several scholars have argued that since the book includes a presentation of Newton’s calculus concepts and techniques, and since the notes were written before Leibniz’ own development of calculus concepts and techniques, it is virtually certain that the这个是Several scholars 的结论 traditional view is false.  这个是Historian的结论A more cautious conclusion than this指的是traditional view is false说明之前的结论不谨慎，也就是反驳 is called for, however第二个转折.  Leibniz’ notes are limited to early sections of Newton’s book, sections that precede the ones in which Newton’s calculus concepts and techniques are presented.

两个黑体字之间只有一个转折，说明两个黑体字是相悖的。

实际上有三个结论，第一个是传统的说independent，第二个是Several scholars 的说传统的是错的，证据包括第一个黑体。第三个才是Historian的，说第二个不严谨，证据是最后的黑体。

个人愚见

多谢啦~现在明白了