Final answer:
C. The 'VALUES' keyword is not used in the INSERT command when retrieving data from another table; instead, a SELECT statement is used to specify the data.
Step-by-step explanation:
The keyword that is not included in the INSERT command when the data is being retrieved from another database table is c. VALUES. The VALUES keyword is used when inserting data directly by specifying the data items to be inserted. However, when inserting data from another table, the data is specified by using a SELECT statement instead of the VALUES keyword. For example, an INSERT INTO command that gets data from another table might look like this:
INSERT INTO table1 (column1, column2)
SELECT column1, column2
FROM table2;
The SELECT statement specifies which data to retrieve from the source table, so the use of VALUES is not necessary.
The SELECT keyword is not included in the INSERT command if the data is being retrieved from another database table. The SELECT keyword is used to retrieve data from one or more tables, but it is not required in an INSERT command when the data is already being retrieved from another table.