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CEMC Gauss (Grade 7), 1998

Combinatorics Difficulty 2.0 Junior Find the answer Canada

The letters of the word 'GAUSS' and the digits in the number '1998' are each cycled separately and then numbered as shown.
1. AUSSG 9981
2. USSGA 9819
3. SSGAU 8199
etc.
If the pattern continues in this way, what number will appear in front of GAUSS 1998?

(A) $4$ (B) $5$ (C) $9$ (D) $16$ (E) $20$

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