Correct Answer - Option 2 : 6

**Given:**

Number = 18345 mn

**Concept used:**

For a number to be divisible by 9 the sum of digits must be divisible by 9

**Calculation:**

Sum of digits = 1 + 8 + 3 + 4 + 5 + m + n

⇒ Sum of digits = 21 + m + n

For min value of m + n

21 + m + n = 27

∴ m + n = 6