The correct answer is C) in parallel. When two generators are connected across a shared load, they are said to be operating in parallel. This means that the generators are connected to the same electrical bus or distribution system, allowing them to share the load equally. Operating generators in parallel allows for increased reliability, redundancy, and the ability to meet higher electrical demands than a single generator could handle on its own. The other options are incorrect because: A) "in resonance" refers to a specific electrical phenomenon not related to parallel generator operation, B) "in frequency" is not a standard term used to describe the relationship between generators, and D) "in series" would involve connecting the generators one after the other, which is not the typical configuration for sharing a load.