Asked by AKSHAY GURU VARADHARAJAN · SRI CHAITANYA TECHNO SCHOOL, JAYANTI NAGAR.
Answer: A. 3
After swapping the hundreds and tens digits: 345->435, 721->271, 864->684, 173->713, 212->122. In descending order: 713, 684, 435, 271, 122. The third largest is 435, and its middle digit is 3.
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