<img src="https://static.zxtiku.com/wangke/imgs/topic/841fcf67f98b0fa0e6faa89b82172e22.jpg"/>为有界信号，则<img src="https://static.zxtiku.com/wangke/imgs/topic/a9850f55705a5ea939f1222daca8041e.jpg"/>=（）。<br/> A、<img src="https://static.zxtiku.com/wangke/imgs/topic/a394cc05884c41cc217fa6c73b95ead8.jpg"/><br/> B、<img src="https://static.zxtiku.com/wangke/imgs/topic/441e8b07ef52e49ec6d9598e371270f5.jpg"/><br/> C、<img src="https://static.zxtiku.com/wangke/imgs/topic/54fbeff5763793906ca9c496de7b0530.jpg"/><br/> D、<img src="https://static.zxtiku.com/wangke/imgs/topic/e71e7c728905582642374e82d9cce537.jpg"/>