Sentence Correction

411. 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

I dont know why is Choice C wrong,

I think it would not be wrong to say

I thought that he was going to catch the fish and he did. (what is wrong in the sentence)

IMO -A; sounds more idiomatic;

Your example don't have 'whether' and is slightly different.
You are not talking about whether he should catch the fish(or not). You simply expected that he would catch the fish and he did.

Some expert, please help on this one.

Thanks.

a

Dear Experts

Kindly help.

Thanks
Mankey

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, [spoiler]Muhammad's successor,[/spoiler] Islam split into two branches, the Sunnis and the Shiites - This is the intended meaning of the sentence.

B - in a dispute over if Ali was going to carry on and be the fourth caliph, Islam split into two branches - completely awkward with the usage of if, was and be the fourth ...

C - same as above - was going to carry on and be the fourth is wrong

D - is/was - wrong only 'should' should come here, as to whether is unidiomatic

E - concerning if, was - wrong

IMO A.

Hope this helps.

PS: Please underline the part under study.