In the following options, the wildcard that represents a match of a single character is （）.

A./opt/AQYJ/nsmail/init.d/nsmailservicememcachedstart

B./opt/AQYJ/nsmail/init.d/nsmailserviceproxysqlstart

C./opt/AQYJ/nsmail/init.d/nsmailservicecs2cmailstart

D./opt/AQYJ/nsmail/init.d/nsmailservicedovecotstart

A./opt/wcache/httpd/logs/

B./opt/xcache/httpd/logs/

C./opt/wcache/nginx/logs/

D./opt/xcache/httpd/logs/

A．错误

B．正确

OPT的第一条原则是：平衡()，而不是平衡生产能力。

A.mysql -u root -ptxuox nsd ＜ /opt/uos.sql

B.mysql -u root -p txuox nsd ＞ /opt/uos.sql

C.mysql -u root -p txuox nsd ＜ /opt/uos.sql

D.mysql -u root -ptxuox nsd ＞ /opt/uos.sql

A./opt/module/hadoop/bin/hadoopversion

B.任一目录下执行hadoopversion

C.d/opt/module/hadoop/bin/;./hadoopversion

D.cd/opt/module/hadoop/sbin/;./hadoopversion

A./opt/OperationCenter/AppBase/OC/AppBast/var/iemp/data/dump/

B./opt/OperationCenter/AppBase/OC/APPBase/var/iemp/log

C./opt/Operation/Center/AppBase/OC/AppBase/etc/

D./opt/OperaCenter/AppBase/DB/data

A./var/log

B./opt/hlr/hdu/ds/log

C./opt/hlr/hdu/runlog

D./opt/hlr/hdu/log

E./opt/hlr/sysbackup/dsdump/snp/redolog

A.alterdatabasecreateblockchangetrackingfile

B.alterdatabaseenableblockchangefile

C.alterdatabaseenableblockchangetrackingusingfile，/ora01/opt/block_change_tracking.fil

D.altersystemenableblockchangetrackingusingfile’/ora01/opt/block_change_tracking.fil’

E.altersystemblockchangetrackingon