CEMC Fermat, 2000

Number theory Difficulty 3.0 AMC 10/12 Find the answer Canada

If the expression $15^6 \times 28^5 \times 55^7$ was evaluated, it would end with a string of consecutive zeros. How many zeros are in this string?

(A) $10$ (B) $18$ (C) $26$ (D) $13$ (E) $5$

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