Final answer:
Two quotations from Anne Frank's diary support the central idea that she has no close friend.
Step-by-step explanation:
The two quotations from Anne Frank's diary that best support the central idea that she feels she has no really close friend are option b and option c. Option b states, "I know about thirty people whom one might call friends..." which implies that Anne has many acquaintances but no truly close friend. Option c states, "I have strings of boy friends, anxious to catch a glimpse of me and who, failing that, peep at me through mirrors in class." This suggests that Anne has many admirers, but none of them are genuine friends.
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