by a group of children，the old man was delighted.
A. To be surrounded
B. Surrounding
C. Surrounded
D. To be surrounding
网友回答
A. To be surrounded
B. Surrounding
(答案→)C. Surrounded
D. To be surrounding
解析：考查分词用法。The old man与Surround构成被动关系，所以使用过去分词。A项的不定式表示将来。