If 1 is added to each odd digit and 2 is subtracted from each even digit in the number 6318574, how many digits will appear more than once in the new number thus formed?​

Correct option is A

Given a number: 6318574
If the digit is odd → add 1
If the digit is even → subtract 2
Original number: 6 3 1 8 5 7 4
Now process each digit:
6 → even → 6 − 2 = 4
3 → odd → 3 + 1 = 4
1 → odd → 1 + 1 = 2
8 → even → 8 − 2 = 6
5 → odd → 5 + 1 = 6
7 → odd → 7 + 1 = 8
4 → even → 4 − 2 = 2
New number: 4 4 2 6 6 8 2
Now count the digits:
2 appears → 2 times 
4 appears → 2 times 
6 appears → 2 times 
Digits that appear more than once: 2, 4, 6 → Total = 3 digits
Correct answer is (a) Three