All of the following are good application data input controls, EXCEPT:

Question $6$ options:

Database operatives $($such as $*,=,$ or$,$ select$)$ should be allowed as valid input

Duplicate entries should not be allowed for data that is intended to be unique.

Execution of a transaction should not be allowed until valid data is entered into each required field.

Fields that are intended to contain only numbers should not allow entry of alphanumeric characters.