Need help with GMAT CR Question.

[chandrabose]

All students at XXXXXXXX College were asked to label themselves conservative, liberal, or middle-of-the-road politically. Of the students, 25 percent labelled themselves conservative, 24 percent labelled themselves liberal, and 51 percent labelled themselves middle-of-the-road. When asked about a particular set of issues, however, 77 percent of the students endorsed what is generally regarded as a liberal position.
If all of the statements above are true, which one of the following must also be true?
(A) All students who labelled themselves liberal endorsed what is generally regarded as a liberal position on that set of issues.
(B) More students who labelled themselves middle-of-the road than students who labelled themselves liberal opposed what is generally regarded as a liberal position on that set of issues.
(C) The majority of students who labelled themselves middle-of-the-road opposed what is generally regarded as a liberal position on that set of issues.
(D) Some students who labelled themselves conservative endorsed what is generally regarded as a liberal position on that set of issues.
(E) Some students who labelled themselves liberal endorsed what is generally regarded as a conservative position on that set of issues.

[Admin]

The answer is D.

 All the questions were on  political  issues .
  25% were conservatives
  24% were liberal
  51% Middle of the road.

  When a particular set of questions among those political questions were put, (quite a few ) 77% have taken a stand as liberals. Now let us leave out the liberals and consider the remainng 53 who are both conservatives and middle of the road mix.

Answer A is truistic as liberals voted for a liberal cause.
Answer B is irrelevant as  there is no mention of opposition.
Answer C is a contradiction as liberals do not oppose what is liberal.
D is correct because even if all the liberals and middle of the road voted for the liberal cause ,  there are 2 more required to make up 77% .
E is meaningless.