The best answer here is chronologically. If we read the excerpt, we can see that the author is starting at the beginning and following a timeline to describe each thing about Gertrude Belle Elion. The other options don't make much sense because there are no interviews cited, though there was obviously come research done. Cause and effect doesn't make sense because there isn't any sort of indication of the causes and effects of certain things except at the end when we find out she never earned her doctorate. The same holds true for problem-solution.
D. she ended the relationship
Explanation:
you need to write a summary on your own. ( story)
then you have to answer the question.
For example: where does the story take place.