What does the term "bracing" refer to in line construction?

Bracing in line construction specifically refers to the reinforcement of structures to ensure they can withstand various environmental forces, such as wind and other stresses. This reinforcement is critical for maintaining the structural integrity and stability of poles, towers, and other support structures used in overhead line construction. Proper bracing prevents these structures from swaying or collapsing under load, contributing to the safety and reliability of the electrical distribution system.

The other options do not accurately define bracing in this context. Joining lines together pertains to ensuring safe connections, insulating wires involves protecting conductors from moisture to avoid electrical faults, and creating a straight line for installation relates to the alignment process rather than structural support. Each of these areas is important in construction and electrical work, but they do not capture the essence of what bracing specifically addresses.