Which command allows for retrieval of all rows from both entities in SQL?

The command that allows for the retrieval of all rows from both entities in SQL is "WITH." In SQL, when using common table expressions (CTEs), the "WITH" clause is utilized to define temporary result sets that can be referenced within the existing SQL statement. This functionality is particularly useful when you want to join multiple tables or entities and need to simplify complex queries by breaking them down into more manageable parts.

Using the "WITH" clause effectively allows developers to organize their queries for better readability and maintainability. By selecting all rows from multiple entities, it facilitates gathering comprehensive data for analysis or further operations.

In contrast, other options that do not include the "WITH" keyword would not properly establish the context necessary for retrieving data from multiple sources in SQL. Therefore, the command "WITH" is crucial and correct in this instance as it enables versatile data retrieval techniques.