Question: Why would you use a common table expression (CTE)?

1. To define queries for later reuse for the duration of the current session
2. To create temporary tables that can be used to pre-select often-used result sets.
3. To calculate a new single value from a result set and return it to the query parser.
4. To break down complex queries and allow reuse within a query.

Answer: The correct answer of the above question is Option D:To break down complex queries and allow reuse within a query.