For what two specific reasons are control lines used?

Control lines are primarily used in operations to accept the load and control travel. This means that they play a critical role in managing the movement of the load being handled, ensuring that it can be lifted, lowered, or moved with precision. By accepting the load, control lines allow operators to maintain better control over heavy or cumbersome objects, reducing the risk of accidents and ensuring operational efficiency.

The correct answer highlights how control lines contribute to the safe and effective handling of loads, which is essential in many operational environments such as construction, rescue operations, or equipment handling. This capability ensures that the movement of loads can occur without unexpected shifts or slips, which is crucial for both safety and productivity.

Other options may refer to important operational aspects, but they do not specifically capture the primary functions of control lines related to the load handling mechanics. For instance, while safety is a crucial aspect of operations, the specific utility of control lines focuses on their role in managing load movement rather than general safety or communication purposes.