from the top of the tower, the east foot of the mountain is a sea of rape flowers.
A. Seen
B. Seeing
C. Having seen
D. To see
网友回答
(答案→)A. Seen
B. Seeing
C. Having seen
D. To see
解析：考查分词做状语。当分词做状语时，如果动词与句子主语构成被动关系，就使用过去分词。如果二者构成主动的关系，就使用现在分词的形式。本的see与the east foot of the mountains构成被动关系，所以使用过去分词的形式。故A正确。