Youareoperatingyourdatabaseinthemanualarchivingmode.Currently，yourdatabaseisconfiguredwiththefollowingonlineredologgroupsandmembers：YoutriedtodropGroup1fromthedatabasebutreceivedthefollowingerrors：ORA-01623：log1iscurrentlogforthread1cannotdropORA-00312：onlinelog1thread1：’D：\ORACLE\ORADATA\TESTDB\REDO01a.LOG’Whatmightbethereasonfortheseerrors？（）

A.Group1isanactiveorcurrentonlineredologgroup.

B.Group1isaninactiveonlineredogroupthathasnotbeenarchivedyet.

C.ThemembersoftheGroup1aretemporarilyasymmetricwiththemembersofothergroups.

D.ThesizeoftheonlineredologmembersofGroup1isdifferentfromthesizeofthemembersinothergroups.