According to a panel of health officials, there has been a great deal of confusion in the medical profession about whether obesity is a biological disorder posing serious health risks or a condition more related to appearance than to health.

A about whether obesity is a biological disorder posing serious health risks or a condition more related to appearance than to

B with respect to obesity being a biological disorder posing serious health risks or if it is related more to appearance than 

C over whether or not obesity is a biological disorder posing serious health risks or it is a condition more related to appearance than to

D about obesity and if it is a biological disorder posing serious health risks or a condition more related to appearance than to

E concerning whether obesity is a biological disorder posing serious health risks or it is a condition more related to appearance than

答案是A，如果是A，不就是介词about 后跟一个句子了嘛？是这个句子做宾语？

通过比较选项，只有A最好了。

E为何不可呢？

感觉A的whether。。。or不对称啊，而且最后一个to似乎不必要？

我觉得还是A好些吧，

与E的比较：concerning whether obesity is a biological disorder posing serious health risks or it is a condition more related to appearance than

首先，“it is”没必要再重复了吧，已经很明确了

然后，“to”应该还是需要的，否则感觉语义读上去不是很明了，而且有与“related”比较的错觉

另外，有一点，希望大家指点啊~白勇上好像说过，标准书面语倾向于用about,而不使用concerning,很久没看这本书了，所以我暂时只找到了一个例子，也不知道可不可行，请大家拍砖啊~

The current administration ,being worried over some foreign trade barries being removed and our exports failing to increase as a result of deep cuts in the value of the dollar ,has formed a group to study ways to sharpen our competivities.

它的正确选项是：worried about the removal of some foreign trade barries and the failure of our exports

另一错误选项是：because of its worry corcerning the removal of some foreign trade barries ,also concerning the failure of our exports 

虽然，这个点，不是这个句子的致命伤，但BY明确说了这个点