Youhavelostallyouronlineredologs.Asaresult，yourdatabasehascrashed.Youhavetriedtorestartthedatabaseandcleartheonlineredologfiles，butwhenyoutrytoopenthedatabaseyougetthefollowingerror.
SQL>startupORACLEinstancestarted.
TotalSystemGlobalArea167395328bytesFixedSize1298612bytesVariableSize142610252bytesDatabaseBuffers20971520bytesRedoBuffers2514944bytesDatabasemounted.
ORA-00313：openfailedformembersofloggroup2ofthread1ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02a.logORA-27037：unabletoobtainfilestatusLinuxError：2：NosuchfileordirectoryAdditionalinformation：3
ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02.logORA-27037：unabletoobtainfilestatusLinuxError：2：NosuchfileordirectoryAdditionalinformation：3
SQL>alterdatabaseclearlogfilegroup2；alterdatabaseclearlogfilegroup2*ERRORatline1：
ORA-01624：log2neededforcrashrecoveryofinstanceorcl（thread1）ORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02.logORA-00312：onlinelog2thread1：，，/oracle01/oradata/orcl/redo02a.log
Whatstepsmustyoutaketoresolvetheerror？（）
a.Issuetherecoverdatabaseredologscommand.
b.IssuetheStartupMountcommandtomountthedatabase.
c.Restorethelastfulldatabasebackup.
d.Performapoint-in-timerecovery，applyingallarchivedredologsthatareavailable.
e.Restoreallarchivedredologsgeneratedduringandafterthelastfulldatabasebackup.
f.Openthedatabaseusingthealterdatabaseopenresetlogscommand.
g.Issuethealterdatabaseopencommand.