One governing factor when determining the minimum size of conduit to be used is the A length of the conduitB presence of waterC conductor fillD location?

The minimum size of conduit to be used is primarily determined by the C conductor fill. This refers to the amount of space the conductors occupy within the conduit, ensuring that there is enough room for heat dissipation and to prevent damage to the conductors. Compliance with the National Electrical Code (NEC) specifications for conductor fill is essential for safety and efficient operation.