Definition: In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D".
Input: [header] How to get an automatic and correct flash sight picture and an automatic and correct sight picture with p&s [title] Learn to aim. [step] Aiming involves sight alignment and sight placement. [title] Learn what sight alignment is. <sep> (A) [step] Sight alignment is the placement of crosshair lines on the ground. This enables sighting to identify sights for target conditions or to guide crosshairs over distance. (B) [step] This is similar to the physical method, but your shooting sight will have the graphics shown on the display of the screen, such as balance, dotted light, a branch at the prime. This has many uses for one rifle, such as allowing you to be no more than 7 feet (2 meters) off the ground, well-controlled, target. (C) [title] Learn the control positions that occur in a snappose click and hold steady target hold. [title] Learn which mode to use with a picture splitter. (D) [step] Sight alignment is the centering of the front blade in the rear sight notch, and the raising or lowering the top of the front sight so it is level with the top of the rear sight. [title] Sight placement is the positioning of the weapon's sights in relation to the target.
Output:
D