According to dictionary, which of the following word will come at LAST position?
1. Operation
2. Orderly
3. Openly
4. Opulent
5. Oral

First letter of all the words are same so verifying the second letter.

The second letter of Orderly, Oral is 'r' which is after 'p' in alphabetical order. So Orderly and Oral are placed after Operation, Openly and Opulent.

Among Orderly and Oral, the third letter of Oral is before Orderly in the alphabetical order. So Oral is placed fourth and Orderly is placed fifth.

$$\therefore\ $$Orderly will come at last position according to dictionary order.

Hence, the correct answer is Option B