The answer is A.
It can't be B because it's not an imaginary tale since it's about her childhood. Not a long and interesting joke because it's about her childhood, and not a joke. And not D because it's not factual.
Upsetting because she was upset by the end of the story
A. Individual productivity is necessary for group productivity.
NOT:
<span>B. Waste isn't a problem in reaching group goals.C. Sacrifice isn't necessary to achieve group goals.
D. Individual productivity is more important than group productivity</span><span>
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