Which of the following is a characteristic of aluminum bus work in substations?

Aluminum bus work in substations is known for its high resistance to corrosion, particularly in specific environments. Aluminum naturally develops a thin oxide layer when exposed to air, which protects the metal underneath from further oxidation. This characteristic makes aluminum an excellent choice for applications where exposure to moisture and other corrosive agents is a concern. By using aluminum bus work, substations can benefit from reduced maintenance and extended service life compared to some other materials.

While cleaning before terminal attachment, performance under high moisture conditions, and the need for varied compositions of filler metal are relevant considerations for bus work, they do not specifically highlight the standout quality of aluminum's corrosion resistance in the contexts where it is most effective. Therefore, its ability to resist corrosion in specific environments is the defining characteristic that reinforces its use in infrastructure like substations.