Explanation:

- Interpreter: This tool executes code line-by-line, translating it into machine-readable form on the go. It's not used for creating executable programs from object files.

- Compiler: This converts source code into object code, but it doesn't combine them into a single executable. The output is usually in a format that still requires linking.

- Linker: This is the tool responsible for combining various object modules and libraries into a single executable. It resolves references and ensures everything is correctly connected.

- Loader: This loads the executable program into memory, preparing it for execution. It doesn't combine object modules.

- Correct Answer: Linker