NEC Article 300.20 addresses which aspect of conductors?

NEC Article 300.20 specifically addresses the requirements related to conductor installation and the considerations for conductors that are used in various applications. The main focus of this section is on the allowable voltage drop and the impacts this has on physical installation and electrical performance, which relates directly to the electrical conductivity of materials used for conductors. Conductivity is a key factor, as it determines how efficiently electricity can flow through the conductor, and thus, it must be carefully considered in installations to ensure safety and efficiency.

The other options touch on important topics but do not directly pertain to what Article 300.20 specifically covers. Temperature ratings, insulation types, and maintenance accessibility are indeed important aspects in the realm of electrical installations but are addressed in other sections of the NEC. Therefore, the emphasis on conductivity in Article 300.20 is what makes this answer the strongest choice in the context of the NEC guidelines.