根据材料内容选择最佳答案。

    This is Cara and Ben. They are twins(双胞胎). They are twelve. This is their bedroom. It's a nice room. There aretwo beds in the room. The yellow bed is Cara's and that green one is Ben's. Thetwins have one desk and two chairs. The chairs look the same. Cara's sweater ison his bed. Ben's coat is on his chair. Their clock, books and pencil-cases areon the desk. Their school bags are behind the chairs.