Which type of data refers to inputs that are expected to be used correctly within the software?

Normal data refers to inputs that are considered valid and within the expected parameters of the software's functionality. This type of data is what the system is designed to handle under regular operating conditions. When software is developed, it is programmed to process this kind of input effectively, ensuring that the application performs as intended.

Using normal data is essential for testing because it allows developers to confirm that the software behaves predictably when given inputs that fall within the standard range. This includes typical values that a user might enter and that the program is expected to manage without errors.

In contrast, error data would consist of inputs that are incorrect or might cause the system to fail. Extreme data involves values at the boundaries of expected ranges, while unusual data refers to inputs that are not typical but still valid. These categories are important for testing edge cases and error handling, but they do not represent the regular operational inputs that the software requires for normal functioning. Thus, normal data is correctly identified as the type of input the software is designed to use properly.