Which keyword is used to prevent any changes in the variable within a C program?Answer areaa) immutableb) mutablec) constd) volatile

Answer

The keyword used to prevent any changes in the variable within a C program is c) const.

The const keyword specifies that a variable's value cannot be modified after its declaration. This can be particularly useful for defining constants or protecting variables from unintended changes, thereby aiding in maintaining integrity and clarity in code. For example, when you declare a variable as const int x = 10;, any attempts to change x later in the code will result in a compilation error. This ensures that the value of x remains constant throughout its scope.

In contrast:

• a) immutable and b) mutable are concepts more commonly associated with object-oriented programming rather than C.
• d) volatile is used to inform the compiler that a variable may change at any time without any action being taken by the code the compiler finds nearby, thus preventing optimization of that variable.

Thus, the right choice is c) const.