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Combinatorics Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

Debanshi has a bag of 18 balls, numbered from 1 to 18. What is the smallest number of balls she would have to remove to be sure that at least three of them displayed primes?

(A) $11$ (B) $12$ (C) $13$ (D) $14$ (E) $15$

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