Define 'line-set' in a fly system.

• A. The combination of a control line, pulleys, and counterweights that moves a single batten.
• B. A single rope used to tie down props.
• C. A plan for lighting notes.
• D. A type of scene change prop.

Answer: (A)

Line-set in a fly system is a complete counterweight-driven unit that moves a single batten. It includes the control line, the pulley assembly (headblock and loft blocks), and the counterweights that balance the load on the batten. This balance lets you raise and lower scenery or other elements smoothly and safely. The described option matches this idea by naming the combination of a control line, pulleys, and counterweights that moves one batten. The other choices describe unrelated items—a tie-down rope, a lighting plot, or a scene-change prop—and don’t represent the mechanism used to lift and lower scenery.