单选题Do you know how much

问题补充：

单选题Doyouknowhowmuchtimeandefforttheydevoted________suchacomplicatedproject?A.to pletingD.to completing

答案：

D解析考查非谓语动词。定语从句的谓语动词与前面的先行词之间构成devote time and effort to doing sth.故