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Answer:</h2>
A data <u>validation</u> rule would prevent a user from entering text in a date/time field.
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Explanation:</h2>
Data validation is used to ensure the entered data is in correct format. Validating is checking the meaning, format, security of the system. This validation will be implemented in the software programs as part of design and operations phase of the software development life cycle. They can be designed through data integrity, procedure-based business rules.
There are different types of validations based on the requirements of the software specifications like date/time, data type, range, uniqueness etc. This process of validation is followed by verification where various actions like advisory, enforcement, etc., take place.