Tom's hair is shorter than------ A.Sam and Bill B.Sam and Bill's C.Sam and bill D.Sam's and Bill's 我认为应该选B,比较级是两者之间的.如果选

Tom's hair is shorter than------ A.Sam and Bill B.Sam and Bill's C.Sam and bill D.Sam's and Bill's 我认为应该选B,比较级是两者之间的.如果选D应该用最高级啊!可是老师说选D