15. The main purpose of the seventh paragraph (the highlighted phrase) is to:

Answer and Explanation

Your Answer is

Correct Answer is C

Explanation

A lot of pages describe how the elders of the Indian tribe helped scientists find the blue star, a plant that was thought to be extinct. The last sentence shows that the (Indian) elders have more knowledge about animals and plants than the library. The gist of this paragraph is that the author can learn more from Indian elders than from libraries.

Item AB: It has nothing to do with the subject of this paragraph.

Item D: It is not mentioned in the text.