题目内容：
White smoke__________25～30 meters above the hill as they approached it.A. has been seen rise
B. had been seen rising
C. was seen rise
D. was seen rising
参考答案：
答案解析：
单选题：White smoke__________25～30 meters above the hill as they app
- 题目分类：英语
- 题目类型：单选题
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A. has been seen rise
B. had been seen rising
C. was seen rise
D. was seen rising