Which type of numerical data type is used for whole numbers?

The correct choice is related to the type of numerical data that is specifically designed to represent whole numbers without any fractional component. An integer is a data type used in programming that encompasses positive numbers, negative numbers, and zero, but does not include any decimals or fractions.

In many programming languages, integers are utilized for operations that require counting, indexing, and performing arithmetic without the need for fractional values. This makes them particularly useful for tasks where whole numbers are a necessity, such as looping a specific number of times or storing quantities.

Other data types listed do not serve this purpose. For example, float and double are both types that can represent numbers with fractional components, making them suitable for real numbers but not for whole numbers specifically. A string, on the other hand, is a sequence of characters and is not used for numerical calculations at all. Thus, the integer type is uniquely suited to handle whole numbers.