One advantage of using ACSR instead of copper conductors for a distribution line is:

Using ACSR (Aluminum Conductor Steel Reinforced) conductors instead of copper for distribution lines has several advantages, particularly in terms of mechanical properties. ACSR consists of an outer layer of aluminum wires surrounding a core of steel wires. This construction provides ACSR with greater mechanical strength compared to solid copper conductors.

The steel core significantly enhances the strength-to-weight ratio, allowing ACSR conductors to span longer distances without sagging or requiring additional support structures. This makes ACSR particularly useful in overhead transmission and distribution lines where minimizing the number of poles or supports is beneficial.

While copper does offer higher conductivity, ACSR is favored for its durability and strength, which can be more advantageous in outdoor environments and areas subject to adverse weather conditions. The combination of aluminum and steel in ACSR makes it particularly suitable for applications where both strength and weight considerations are crucial. This is why the option regarding greater mechanical strength stands out as a primary advantage of using ACSR over copper conductors.