The schoolboys and schoolgirls are walking along the street, ___

The schoolboys and schoolgirls are walking along the street, _____ a small redcap.
A、each of them has
B、they each have
C、every wears
D、each wearing
【正确答案】：D
【题目解析】：前半句是完整的句子，说明后半句中不能有谓语动词，非谓语现在分词表状态。