Final answer:
A reference parameter is an alias for its corresponding argument and is indicated with an ampersand (&) after the type in C++ function prototypes.
It allows the function to modify the original argument directly and can be modified unless it's declared as const.
Therefore, the correct answer is: option d). Both is an alias for its corresponding argument and is declared by following the parameter's type in the function prototype by an ampersand.
Step-by-step explanation:
A reference parameter in a function is a parameter that refers to the same memory location as its corresponding argument. This means that changes made to the reference parameter affect the original argument.
In programming languages such as C++, a reference parameter is indicated by using an ampersand (&) after the data type in the function prototype or function definition.
It is indeed an alias for its corresponding argument, allowing the function to modify the argument directly. Therefore, a reference parameter can be modified unless it is explicitly declared as const.
For example, consider the following function:
void increment(int& num)
{
num++;
}
If we call this function with a variable x as the argument, such as increment(x);, the value of x will be incremented by 1.