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Let $d$ be the number of positive square integers (that is, it is a square of some integer) that are factors of $20^5\times21^5$. Which of the following is true about $d$?

(A) $50 \leq d < 100$

(B) $100 \leq d < 150$

(C) $150 \leq d < 200$

(D) $200 \leq d < 300$

(E) $300 \leq d$
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