What is the role of the `const` keyword in C?

The correct answer highlights the role of the const keyword in C, which is to define a variable whose value cannot be changed after it has been initialized. When you declare a variable with the const qualifier, you inform the compiler that this variable is read-only. Any attempt to modify the value of a const variable will result in a compilation error, helping to prevent unintentional changes and maintain the integrity of the data.

For example, if you define a variable as const int x = 10;, trying to execute x = 20; later in the program will lead to an error, reinforcing that the value of x should remain constant throughout its scope.

This principle is crucial for maintaining stability in programs, particularly when dealing with values that are meant to be fixed, such as configuration settings or constants in calculations. It improves code reliability and clarity by clearly indicating which variables are intended to remain unchanged.