求解！！

dedeyuky

In the late seventh century， in a dispute over whether the Prophet Muhammad's son-in-law， Ali， should carry on as the fourth caliph， Muhammad's successor， Islam split into two branches， the Sunnis and the Shiites.
(A） over whether the Prophet Muhammad's son-in-law， Ali， should carry on as the fourth caliph， Muhammad's successor
（B） over if Ali， the Prophet Muhammad's son-in-law， was going to carry on and be the fourth caliph， Muhammad's successor
（C） over whether Ali， the Prophet Muhammad's son-in-law， was going to carry on and be the fourth caliph， Muhammad's successor
（D） as to whether the fourth caliph， Muhammad's successor， is to be the Prophet Muhammad's son-in-low， Ali
（E） concerning if the fourth caliph， Muhammad's successor， was to be the Prophet Muhammad's son-in-law， Ali

答案：A。 为什么不选B么？

xht0812

B中carry on and be累赘，介词后if用的欠妥；A最为简洁明确，DE介词用的不对直接剔除

bull113

书面英语,一般用WETHER,不用IF

dedeyuky

谢谢两位NN！！