Answer: Indexed
Explanation: Indexed property in the database system is for indexing .In this process reduction of the record/disk numbers results in the increase in the optimized performance. The structure of the index is in column form.
This technique rapidly provides the data from the table containing database when every query arises or requirement is proposed. Therefore the efficiency of the database increases.
Other options are incorrect because validation rule and text are regarding the verification of the data user and text respectively and expression is defined as the group of one or more value.Thus the correct option is indexed.
