用rpm查询系统中是否安装了firefox浏览器，下面做法正确的是：

A.rpm -q firefox

B.rpm -l firefox

C.rpm --list firefox

D.rpm --search firefox

A.rpm –qa | grep vsftpd

B.rpm -a |grep vsftpd

C.service vsftpd start

D.service ftp start

A.rpm –aq

B.rpm –ed

C.rpm –ui

D.rpm -qi

A.rpm -q httpd

B.rpm -e httpd

C.rpm -i httpd

D.rpm -qa httpd

A.FireFox浏览器

B.ie

C.百度

D.QQ浏览器

A.rpm | grep nfs

B.rpm –qf | nfs

C.rpm –q nfs

D.rpm –qa | grep nfs

A.rpm -ih opera-12.16-1860.x86_64.rpm

B.rpm -ivh opera-12.16-1860.x86_64.rpm

C.rpm -i opera-12.16-1860.x86_64.rpm

D.rpm -vh opera-12.16-1860.x86_64.rpm

A.360浏览器

B.chrome浏览器

C.IE浏览器

D.firefox浏览器

A.rpm –qa|grep ‘^htt‘

B.rpm -qa |grep 'htt'

C.rpm -qa |find '^htt'

D.rpm -q|grep '^htt='