Which operation can be used to select a specific set of rows in a table?

The operation used to select a specific set of rows in a table is referred to as selection. In the context of database operations, selection allows you to filter records based on certain criteria, effectively retrieving only those rows that meet the specified conditions. This capability is essential when working with large datasets, as it enables you to focus on a relevant subset of data, improving efficiency and insight during data analysis or application operations.

While other operations like projection focus on selecting specific columns from tables, selection is specifically designed to work on rows. Operations such as Cartesian product and union serve different purposes: the Cartesian product combines all possible pairs of rows from two tables, while the union combines the results of two select queries from tables, including all distinct rows from both queries. Thus, selection is the most appropriate choice for isolating particular rows based on defined criteria.