What is 'compilation' in the context of C++ programming?

Compilation in the context of C++ programming refers to the process of translating the human-readable C++ source code into machine code, which is a binary format that the computer's processor can execute. This process is crucial because computers do not understand high-level programming languages directly; they require instructions in a format that their hardware can process.

During compilation, the C++ compiler performs several tasks, including lexical analysis, syntax analysis, semantic analysis, optimization, and code generation. The output of this compilation is typically an executable file or object file that can be run on the machine.

The other options describe different aspects of software development but do not pertain to compilation. Executing the program refers to running the compiled code, debugging involves finding and resolving errors within the source code prior to compilation, and writing source code is the initial step in the programming process that occurs before any compilation takes place. Thus, the focus on translating source code into machine code clearly defines compilation and demonstrates why this is the correct choice.