According to the NEC®, which combination of bends is permitted in a conduit run between two junction boxes?

The correct response reflects the National Electrical Code (NEC) regulations regarding the allowable number and type of bends in a conduit run. The NEC limits the total number of bends between junction boxes to ensure that a wire can be safely pulled through the conduit without excessive stress or difficulty.

In option B, the combination of two 90-degree bends, one 45-degree bend, and a 12-degree offset adheres to NEC guidelines. The total of bends allows for smooth transitions and easier wire pulling within the electrical conduit system. The 90-degree bends provide a sharp turn, while the 45-degree and 12-degree bends make up for the additional curvature without exceeding the code limit. This combination effectively balances the need for directional changes with the practicality of maintaining the conduit system's integrity.

Each of the other combinations either exceeds the acceptable limit of bends or features angles that can make cable pulling more challenging, which is discouraged by the NEC for efficient and safe installation practices.