Find the rule: (3 / 1 / 4 / 1 = 3 / 4) (9 / 5 / 8 / 5 = 9 / 8) (11 / 7 / 15 / 7 = 11 / 15) (B / A / C / a =?)

B/C
That's the first one / the third one

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