Answer and explanation

Correct answer: A.

  1. Step 1: Powers of repeat every 4 steps; 431 leaves remainder 3 on division by 4.
  2. Step 2: So .
Answer
.
Why not the others: : This is the value of , which belongs to a different remainder on division by 4. : This is the value of , which belongs to a different remainder on division by 4. : This is the value of , which belongs to a different remainder on division by 4.

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