Correct option is C
Original digits: 86 29475
Apply transformation:
8 (even) → 8 + 1 = 9
6 (even) → 6 + 1 = 7
2 (even) → 2 + 1 = 3
9 (odd) → 9 – 1 = 8
4 (even) → 4 + 1 = 5
7 (odd) → 7 – 1 = 6
5 (odd) → 5 – 1 = 4
New number: 9, 7, 3, 8, 5, 6, 4
Highest digit = 9
Lowest digit = 3
Final Answer: 9 + 3 = 12
Final Correct Option: (C)