Which of the following is not a factor in selecting a conductor?

• A. Ampacity and Voltage
• B. Amperage and Resistance
• C. Heating and Cooling
• D. Location and Environmental

Answer: (B)

Conductor sizing is driven by how much current will flow (ampacity) and under what conditions the wire will operate. You need enough ampacity to carry the load without overheating, and you must ensure the insulation and construction are suitable for the system voltage. Heating and cooling matter because the current creates heat, and you have to be able to dissipate that heat in the given environment. Location and environmental factors determine insulation class, guarding, and protection needed for moisture, chemicals, sunlight, or physical hazards.

Amperage is a direct factor because the wire must be able to carry the expected current safely. Resistance, however, is a property that affects performance after the conductor is chosen (it influences voltage drop and heat but is not itself a primary factor used to select the conductor size). So a choice that centers on resistance isn’t describing a direct criterion used in selecting the conductor, making it the not-fit option in this context.