Final answer:
The key benefit of generics is to enable errors to be detected at compile time rather than runtime time.
Step-by-step explanation:
The correct answer is 1) compile, runtime. Generics are a feature in many programming languages that allow code to be written with placeholder types, which can then be specified when the code is used. This helps in creating type-safe code where type compatibility errors are caught during compile time rather than at runtime, which can save developers from encountering unexpected errors and crashes when the application is running.