Two different positions of the same dice are given below. Which is the number on the face opposite to the face containing 10?

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Logic: In these types of dice problems, we should write all three numbers/letters in clockwise or anticlockwise from a fix common number/letter.

11 → 8 → 10

11 → 8 → 12

So, the opposite of 10 is 12.

Thus, correct option is (c).