Twins often complain that people tend to treat them as a pair, ________ individuals.
考查短语词义。选项A. rather than（宁可，而不是）；选项B. better than（超过，多于，好于）；选项C. less than（小于，少于，不超过）；选项D. worse than（不如，比……更差）。所以，根据句意，选A。
【参考译文】双胞胎经常抱怨人们往往把他们当作一对，而不是作为个人看待。