Correct option is C
Given: 846523X7Y is divisible by 9, and Y-X=6
Formula Used: Sum of digits of a number divisible by 9 must be divisible by 9.
Solution:
36 + 6 + X +X= should be multiple of 9.
Let, 41+2X→multiple of 9.
X=2. (only possible)
Y=8.

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