Correct Answer - Option 1 : Copper lugs
Mechanical lugs are available bolted with two screws or with four screws. They are typically ring-shaped and are usually made of high-grade electrolyte copper or aluminum, so these are also called copper lugs.
They are suitable for big wires and cables and are available in three varieties: plain type, sight hole type (which is similar to the plain types, but with a bigger hole), and connector type.
Designed to be easily installed and removed for repairs or maintenance, copper lugs are generally used when permanent, direct-fastening methods are not feasible or necessary.
Copper Lugs may be provided with safety covering to avoid shocks or protective covering to avoid damage to the copper lugs, cables, connectors, and prevent short-circuit.
The commutator segments are connected to the armature conductors by means of copper lugs.