GWD－25-Q24 求教

答案是B，我选的是A, 不理解，请NN指教

24. GWD25-Q24

Although improved efficiency in converting harvested trees into wood products may reduce harvest rates, it will stimulate demand by increasing supply and lowering prices, thereby boosting consumption.

A.   in converting harvested trees into wood products may reduce harvest rates, it will stimulate demand by increasing supply and lowering prices, thereby boosting

B.    in converting harvested trees into wood products may reduce harvest rates, demand will be stimulated because of increasing supply and lowering prices, which boost

C.   of converting harvested trees into wood products may reduce harvest rates, it will stimulate demand by increasing supply and lowering prices, which boosts

D.   of harvested trees being converted into wood products may reduce harvest rates, it will stimulate demand, because it will increase supply and lower prices, thereby boosting

E.    when harvested trees are converted into wood products may reduce harvest rates, demand will be stimulated because of increasing supply and lowering prices, which boost

it没有指代对象，B改成被动很好的解决了这个问题

XDF里面有，指代句子，新名词，或者Ving 不能用which之类的