新pre SC 1-216 请教

216.
            (30280-!-item-!-188;#058&005378)     (T-3-Q39. ��ɽ-7-39)

Plants are more efficient at acquiring carbon than are fungi, in the form of carbon dioxide, and converting it to energy-rich sugars.

A. Plants are more efficient at acquiring carbon than are fungi,

B. Plants are more efficient at acquiring carbon than fungi,

C. Plants are more efficient than fungi at acquiring carbon,

D. Plants, more efficient than fungi at acquiring carbon,

E. Plants acquire carbon more efficiently than fungi,

为什么A选项不好，D和A有什么区别，谢谢

我觉得C表明plants 和 fungi比较，A 中plants的比较对象有歧义，有可能是carbon,如果改成than fungi are 会好吧~~

搞懂了，一语中的！谢谢AlienX