AMI & Mexico Inspection Practice Test

In the Marine Corps, officer ranks map to pay grades from O-1 to O-10. The sequence places O-5 at Lieutenant Colonel, sitting between Major (O-4) and Colonel (O-6). A Lieutenant Colonel is a senior field-grade officer, typically commanding a battalion or serving in a senior staff role at a high level. This is why the rank at O-5 is Lieutenant Colonel. The other options correspond to different pay grades: Major is O-4, Colonel is O-6, and Brigadier General is O-7.