Film has a much shorter history, especially when ________ such art forms as music and painting.
句意：电影的历史的很短，尤其是当把它和像音乐和绘画这样的艺术形式相比时，更要短得多。从句主语也是film，与动词 compare之间存在动宾关系，应该用被动语态。从句完整表达是when it is compared to such art forms as music and painting，主语一致可以省略be动词，故本题答案选D。