GWD一道~

viola1003

Past assessments of the Brazilian rain forest have used satellite images to tally deforested areas,where farmers and ranchers have clear-cut and burned all the trees,but such work has not addressed either logging,which is the removal of only selected trees,as well as surface fires,burning down individual trees but do not denude the forest.

B.which removes only selected trees, or surface fires that burn.

D.removing only selected trees, or surface fires,burning

为什么答案是B呢？请大家指点一下~

connie4895

以下是引用viola1003在2008-11-1 16:29:00的发言：

Past assessments of the Brazilian rain forest have used satellite images to tally deforested areas,where farmers and ranchers have clear-cut and burned all the trees,but such work has not addressed either logging,which is the removal of only selected trees,as well as surface fires,burning down individual trees but do not denude the forest.

B.which removes only selected trees, or surface fires that burn.

D.removing only selected trees, or surface fires,burning

为什么答案是B呢？请大家指点一下~ 必须要和未画线的部份做平衡对称，所以不能选D