Walking around I found the city was full of people for the festival.A. wearingB. had new

问题补充：

Walking around, I found the city was full of people for the festival.

A. wearing

B. had new clothes on

C. dressing up

D. dressed up

答案：

A. wearing

B. had new clothes on

C. dressing up

(答案→)D. dressed up

解析：考查非谓语动词。dressup的意思是：乔装打扮。和被修饰词people之间是被动关系，所以用过去分词作后置定语。句意：四处走走，我发现城市到处是盛装的人们。故D正确。