问题
单项选择题
In each of the following groups of words, there are four underlined letters or letter combinations marked A, B, C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation. Mark your answer by blackening the corresponding letter on the Answer Sheet.（）
A. orange
B. clock
C. bottle
D. color
答案
参考答案：D
解析：
D项中o发
，其他选项都发
。