When a student's aggressive behavior disrupts the classroom, behavior that once might have resulted in that student's expulsion, teachers often refer the child to counselors who can diagnose attention-deficit disorders and other learning disabilities.


(A) behavior that once might have resulted in that student's expulsion, teachers often refer -> "that" modifies "behavior" it is okay and structure wise, it is also good. I didn't get an error. Let's keep it.

(B) behavior that might have resulted once in that student's expulsion, teachers refer often -> Resulted once is incorrect. It is changing the meaning.

(C) which might have resulted once in expulsion of that student, teachers frequently refer -> which is modifying "classroom". Incorrect.

(D) behavior, which once might have resulted in that student's being expelled, disrupts a classroom, teachers frequently refer -> being expelled. It is incorrect.

(E) behavior, which once might have resulted in an expulsion, disrupts a classroom, teachers are apt to refer -> Incorrect.

So, I think A.

When a student's aggressive behavior disrupts the classroom, behavior that once might have resulted in that student's expulsion, teachers often refer the child to counselors who can diagnose attention-deficit disorders and other learning disabilities.


(A) behavior that once might have resulted in that student's expulsion, teachers often refer
Can not see anything wrong here

(B) behavior that might have resulted once in that student's expulsion, teachers refer often
often refer or refer often. I guess often refer. Also once might have or might have once. I will go with once might have resulted. This is why this choice is not preferred over A

(C) which might have resulted once in expulsion of that student, teachers frequently refer
Which refers to classroom and this is incorrect.

(D) behavior, which once might have resulted in that student's being expelled, disrupts a classroom, teachers frequently refer
disrupts a classroom is repeated here. This is already present in the non underlined portion.

(E) behavior, which once might have resulted in an expulsion, disrupts a classroom, teachers are apt to refer
Same as D

Answer: A
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