A rectangular box of lines with the long horizontal side. From left, the first vertical line has a stack of short horizontal lines A, which are from top to bottom short, very short, short, very short. The second and third vertical lines have zigzags as part of them, labeled C. The fourth vertical line has 2 circles marked with X's labeled D. The fifth vertical line has a zigzag. On the bottom side between the first and second horizontal lines labeled B is a small circle with a short line pointing up at about 45 degrees then a gap then another small circle then the line continues. Use the drop-down menus to identify the parts of the diagram labeled A, B, C, and D.

Label A

Label B

Label C

Label D