What type of lead is held plumb or at the desired batter with the second single crane line?

The correct answer is that the type of lead held plumb or at the desired batter with the second single crane line is swinging lead. This is significant in crane operations as a swinging lead allows for the controlled positioning of the load during a lift, maintaining an ideal angle for stability and precision.

When using a swinging lead, the second line functions to stabilize the load and keep it balanced while it is being maneuvered. This technique is important in operations where accurate placement of materials is crucial, such as construction projects or moving heavy equipment. The ability for the lead to swing or pivot helps operators make minor adjustments without the need for a complete repositioning of the crane.

In contrast, the options related to fixed lead, leading, and drop lead do not provide the same level of flexibility and control required for maintaining the desired batter angle and plumb position. Fixed lead is typically rigid and does not allow for swinging, leading refers to the initial direction of the load which does not specifically address the plumb or batter angle, and drop lead emphasizes lowering a load, which does not relate directly to the positioning capabilities provided by a swinging lead.