C++ is the lowest it will take, but you can use C-only-code in a C++ project.
You will have to keep yourself from using enhanced features, but the result can be C.
If you make a Win32 Console App and don't include any additional features, you'll be as close as you can get.
(then just stick to c functions).
You will also need to add a preprocessor definition of "_CRT_SECURE_NO_WARNINGS" so you can use the older style functions without the compiler giving warnings.
Also, I set my character set to Nulti-Byte instead of Unicode.