To get the total quantity sold by each employee, you need:
* An aggregate function to compute the total per group.
* A clause to define the grouping (i.e., "by each employee").
The SQL pattern is generally:
SELECT employee_id,
SUM(quantity) AS total_quantity
FROM sales
GROUP BY employee_id;
* SUM (F) is the aggregate function that adds up all quantity values.
* GROUP BY (D) groups the rows by employee so that SUM is calculated per employee.
Why the other options are incorrect:
* MAX (A) returns the maximum value, not the total quantity.
* SELECT (B) is a SQL keyword for selecting columns, not an aggregate function.
* HAVING (C) is used to filter groups after aggregation, not to perform aggregation itself.
* ORDER BY (E) sorts the result set; it does not calculate totals.
Thus, the functions needed to retrieve the total quantity sold by each employee are GROUP BY (D) and SUM (F).
CompTIA Data+ Reference (concept alignment):
* DA0-001 Exam Objectives - Data manipulation: aggregate functions and GROUP BY.
* CompTIA Data+ SQL sections: examples combining SUM with GROUP BY to summarize data by category (e.g., employee, product, region).