【题目】 The footprints on the floor __________ that someone had broken into their house while they were out.
A. recognized B. forecast C. indicated D. observed
在线课程【答案】C
【解析】
试题分析：A. recognized 识别，辨认；B. forecast 预报；C. indicated 暗示，表明； D. observed 观察，庆祝；根据“地板上的脚印表明他们外出时有人闯入了他们的房子”可知indicate符合语境，故选C。