What is the function of the rifle's rear sight and how is windage adjusted on a typical M4/M16 rear sight?

• A. Elevations adjustments are done with the front sight post.
• B. Windage adjustments are made by turning the rear sight drum or knob to move the point of impact left or right.
• C. Stores ballistic data; windage set in the scope turrets.
• D. Functions as a flashlight mount; windage adjusted by shifting the entire optic.

Answer: (B)