单选题：You want to search the file myfile for all of string containing

You want to search the file myfile for all of string containing at least five characters, where character number 2 and 5 are 'a' and character number 3 is NOT 'b'. Which command would you use?@[B](1)
A. grep a*^b?a myfile
B. grep .a[^b].a myfile
C. grep .[a].*.[a] myfile
D. grep .a*^b..a myfile




A.grep a*^b?a myfile
B.grep .a[^b].a myfile
C.grep .[a].*.[a] myfile
D.grep .a*^b..a myfile


答案：B