If the order in which the candidates speak at meeting 1 is R, U, S, T, Q, and the order in which they speak at meetin...

If b is the correct answer, that would mean R is placed in the third spot. That would mean either Q or U would feel in spots 4 and 5. That is impossible because Q is already in spot 5 in meeting one and U cannot be in spot 5 because it would violate rule 2 which says it must be 1st in at least one other meeting.