单项选择题
A.A4:B6 B.A4:B4 C.B6:A4 D.A6:B4
A.1-3,5-7,20 B.1-3,5,6,7-20 C.1,3-5,6-7,20 D.1,3,5-7,20
A.SUM B.TOTAL C.COUNT D.AVERAGE