Which high side rating indicates there is one high side bushing?

The choice indicating a high side rating that mentions one high side bushing is the one that specifically identifies the bushing arrangement through its designation. In this case, the correct answer shows a voltage rating of 12470 with a ground designation listed as GRDY. This format indicates not only the operating voltage but also specifies that there is a grounded system, which typically implies the use of a single high side bushing as part of a transformer or circuit configuration.

The designation is essential for understanding the equipment's configuration and its appropriate applications. In electrical distribution, having a grounded high side bushing is critical for safety and operational reliability. This confirms that the system has been designed for specific grounding practices, which is crucial for protecting personnel, equipment, and maintaining system balance.

The other options do not mention grounding or bushing configurations in a way that directly indicates a single high side bushing. They represent different voltage levels or configurations, but they lack the explicit detail that connects to the query regarding a single high side bushing. Thus, the choice that articulates both the voltage level and grounding offers a clearer identification of a system with one high side bushing.