下列化合物可用作双烯体的是( )<br/> A、<img src="https://static.zxtiku.com/wangke/imgs/topic/5f6be08b1a505a19f80af0ad4c3e897b.jpg"/><br/> B、<img src="https://static.zxtiku.com/wangke/imgs/topic/52c8e9028c09cd876db48eb9feb80a92.jpg"/><br/> C、<img src="https://static.zxtiku.com/wangke/imgs/topic/3c84289c9ad49dc4a243d7896bb165a1.jpg"/><br/> D、<img src="https://static.zxtiku.com/wangke/imgs/topic/d731f629c2beda842e46d4c83a56752d.jpg"/>