Which query finds the ID, Job_Title, and Salary values of all employees who make more than the average of all employees?

The correct choice effectively retrieves the ID, Job_Title, and Salary of employees whose salaries exceed the average salary of all employees in the staff table.

This option utilizes a subquery to calculate the average salary. The inner query, select mean(Salary) from staff, accurately computes the average salary from the Salary column of the staff table. The outer query then filters the records where the Salary is greater than this computed average, allowing the retrieval of only those employees who earn more than the average.

Other options may not accomplish this goal correctly. The first option incorrectly attempts to calculate the mean within the WHERE clause without considering the context of the entire data set. The second option misses specifying the table from which to calculate the average, making it incomplete. The fourth option erroneously uses max(Salary) instead of the mean, which focuses on finding the highest salary rather than the average, and does not fulfill the requirement to compare to the average salary of all employees.