If an aggregate function is specified in any field, then fields that use criteria must show the __________ keyword on the total line.

• GROUP BY

• ORDER BY

• WHERE

• JOIN

...
Explanation: In a database, an aggregate function is used to perform a calculation on a set of values, such as finding the sum or average of a group of numbers. When an aggregate function is specified in a query, and there are other fields in the query that use criteria (such as a filter), then the query needs to know which data to include in the calculation.

To tell the query which data to include, we use a keyword called "WHERE". The WHERE keyword is used to specify the criteria (or conditions) that must be met in order for a record to be included in the calculation. For example, if we are calculating the average salary of employees, we might only want to include employees who work in a specific department or who have been with the company for a certain number of years. We would use the WHERE keyword to specify these conditions.

On the "total line" of the query (which shows the result of the aggregate function), we need to include the WHERE keyword so that the query knows which data to include in the calculation. If we don't include the WHERE keyword, the query will include all of the data in the calculation, which might not be what we want.
So, in summary: when an aggregate function is specified in a query, and there are other fields in the query that use criteria, we need to include the WHERE keyword on the total line to specify which data should be included in the calculation.