Review the following code:
SELECT pn, vn, sum(prc*qty)
FROM sale
GROUP BY CUBE(pn, vn)
ORDER BY 1, 2, 3;
Which combination of subtotals do you expect to be returned by the query?

A.
(pn,vn)
B.
( (pn,vn),(pn) )
C.
( (pn,vn),(pn),(vn) )
D.
( (pn,vn),(pn),(vn),( ) )