单项选择题TableTAB1wascreatedusingthefollowingstatement:CREATETABLEtab1(c1INT,c2INT,c3INT,c4INT,c5INT);IfcolumnC1isuniqueandqueriestypicallyaccesscolumnsC1,C2andC3together,whichstatement(s)willcreateindex(es)thatwillprovideoptimalqueryperformance?()
A.CREATE UNIQUE INDEX xtab1 ON tab1 (c1); CREATE INDEX xtab2 ON tab1 (c2) INCLUDE (c3)
B.CREATE UNIQUE INDEX xtab1 ON tab1 (c1) INCLUDE (c2, c3)
C.CREATE UNIQUE INDEX xtab1 ON tab1 (c3, c2, c1)
D.CREATE UNIQUE INDEX xtab1 ON tab1 (c2) INCLUDE (c1, c3)