Which of the following describes the voltage in a 3-phase system correctly?

In a 3-phase system, each phase typically carries the same current when the system is balanced. A balanced system occurs when the loads on each phase are equal, leading to uniform current distribution. This is a key characteristic of 3-phase power systems, making them efficient for power generation and transmission.

When analyzing the other options, it's important to note that while each phase voltage can theoretically differ if the loads are unbalanced, the option that accurately captures the fundamental aspect of a balanced 3-phase system is that the current remains consistent across all phases. In addition, 3-phase systems are not connected in series; rather, they operate in parallel, which permits simultaneous power delivery to multiple devices. Lastly, the line-to-line voltage in a 3-phase system is actually higher than the phase voltage and is derived from the phase voltages, not lower, further reinforcing that the correct characterization is about the current being the same across phases.