Normally You would need to simplify all of them, to see what their values are like.
Already from the start, however, we can see that 9n + 3 + 2 and 9n + 11 isnt the same value. Based on this, we should only need to simplify one of the other, to get either 9n + 5 or 9n + 11.
Lets pick the upper one.
(4n + 3) + 5n + 8 - 6 4n + 3 +5n + 2 9n + 5.
This indicated that 9n+11 is the odd one.
To make sure, we can solve the next one: (4n + 5n) + (3 + 8 - 6) 9n + 5 Which indicated the same thing.