A dice has its faces marked by letters K, N, A, B, C and Z. Two positions of the same dice are given below. Which face is opposite to face A?

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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.

Common face to clock wise rotate:

So, Z ​is opposite to face A.

Thus, the correct option is: (a)