【题目】Before our study we did not have data that could tell us __ those changes were small or large .
A. that B. how C. when D. whether
在线课程【答案】D
【解析】句意：在我们研究之前，我们没有数据可以告诉我们这些改变的大小。分析句子结构可知“________ those changes were small or large”为宾语从句，并且该从句成分完整，排除在句中作状语的B、C；that引导名词性从句时，没有实际含义，不合题意。whether意为“是否”，符合题目要求。所以选D。