Which statement is true regarding the CUBE operator in the GROUP BY clause of a SQL statement?

Which statement is true regarding the CUBE operator in the GROUP BY clause of a SQL
statement?

A.
It produces only aggregates for the groups specified in the GROUP BY clause.

B.
It finds all the NULL values in the superaggregates for the groups specified in the
GROUP BY clause.

C.
It produces 2 n possible superaggregate combinations, if the n columns and expressions
are specified in the GROUP BY clause.

D.
It produces n+1 possible superaggregate combinations, if the n columns and expressions
are specified in the GROUP BY clause.