Lots of rescue workers were working around the clock, _____suppl

Lots of rescue workers were working around the clock, _____supplies to Yushu, Qinghai province after the earthquake.


A、sending
B、to send
C、having sent
D、to have sent
【正确答案】：A
【题目解析】：本题考查非谓语动词。句意：地震发生后，大量的营救人员夜以继日地为青海省玉树县提供补给。该空为现在分词短语作伴随状语，故选A项。