In . . . . . . . . , The size of the array can be changed at the run timesize changes during the program execution.

The correct answer is C. dynamic array.

A dynamic array is an array whose size can be changed at runtime. This is in contrast to a static array, whose size is fixed at compile time. Dynamic arrays are useful when you need to store a variable amount of data, such as the number of items in a list.

To create a dynamic array, you use the new keyword. For example, the following code creates a dynamic array of 10 integers:

int[] myArray = new int[10];

Once you have created a dynamic array, you can add items to it using the Add method. For example, the following code adds the number 1 to the myArray array:

myArray.Add(1);

You can also remove items from a dynamic array using the Remove method. For example, the following code removes the number 1 from the myArray array:

myArray.Remove(1);

The size of a dynamic array can be changed at any time using the Resize method. For example, the following code resizes the myArray array to 20 elements:

myArray.Resize(20);

Dynamic arrays are a powerful tool that can be used to store and manage large amounts of data. They are especially useful when you need to store data that is constantly changing.

The other options are incorrect because:

• A. if ... then ..else is a control flow statement that is used to execute different blocks of code depending on the value of a condition.
• B. do while is a control flow statement that is used to execute a block of code as long as a condition is true.
• D. array is a data structure that stores a collection of elements of the same type. The size of an array is fixed at compile time.