一道逻辑推理题，bug了，求解，谢谢咯！

sjlolitaUID: 3156063

A person who agrees to serve as mediator between two warring factions at the request of both abandons by so agreeing the right to take sides later. To take sides at a later point would be to suggest that the earlier presumptive impartiality was a sham.

The passage above emphasizes which of the following points about mediators?

A They should try to form no opinion of their own about any issue that is related to the dispute.
B They should not agree to serve unless they are committed to maintaining a stance of impartiality .
C They should not agree to serve unless they are equally acceptable to all parties to a dispute.
D They should feel free to take sides in the dispute right from the start , provided that they make their biases publicly known.
E They shuold not reserve the right to abandon their impartiality so as not to be open to the charge of having been deceitful.

答案选B 实在搞不懂第一句话的后半部分是什么意思，就是at the request of both abandons  完全晕掉了，求高手指点，谢谢！

米兰啸西风UID: 3136730

1# sjlolita

问题是：上文强调的是mediator的哪一点？

文中说：在双方有争论（dispute）时，mediator可以来帮忙（serve），但是前提是必须做到公正（impartiality）！如果不这样，而是偏袒一方（take sides），就会被放弃（abandon）！

文中只有两句话，第二句是解释第一句末尾的take sides later 的后果：如果这样，之前agree the right 所表现出的 impartiality就是个耻辱！

因此可以看出答案是B