单项选择题

A.SELECT‘2019-81-91"FROMDUAL
B.SELECTTO_CAHR("2919-91-01")FROMDUAL
C.SELECTDATE"2019-01-01"FROMDUAL
D.SELECTTO_DATE("2019-81-81")FROMDUAL
E.SELECTTO_DATE("2019-01-81","YYYY-MM-DD)FROMDUAL