Which two are true about aggregate functions?（）
- A You can use aggregate functions in any clause of a SELECT statement.
- B You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
- C You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
- D You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
- E You can use aggregate functions on a table, only by grouping the whole table as one single group.
- F You cannot group the rows of a table by more than one column while using aggregate functions.