What is the main purpose of the 'else' statement in control flow?

The main purpose of the 'else' statement in control flow is to provide an alternative when prior conditions are false. In a typical conditional structure, such as an if-else statement, the program first evaluates the conditions specified in the 'if' statement. If this condition evaluates to false, the control flow moves to the 'else' statement, allowing the program to execute a different block of code that serves as an alternative path.

This functionality is crucial for managing different outcomes based on varying conditions. It enables the programmer to specify what should happen when the initial condition (or conditions, if there are multiple if-else statements) is not met, thus allowing for more robust and flexible code.

Taking this into account, the options that pivot on different functionalities of the control flow do not fit the precise role of 'else.' It's not about executing when all previous conditions are true, terminating the control flow, or further separating logical conditions; these aspects are managed by different structures and logic in programming. The 'else' statement specifically addresses scenarios where prior conditions are not fulfilled, ensuring the program can still respond correctly under those circumstances.