My brother ___________ while he ___________ his bicycle and hurt

My brother ___________ while he ___________ his bicycle and hurt himself.
A、fell ;was riding
B、fell ; were riding
C、had fallen ; rode
D、had fallen; was riding
【正确答案】：A
【题目解析】：句中的连词while意为“当……的时候”，常常引导过去进行时的句子。