Powerscore practice question

Is it B

i m stuck between b n c

i will go with B

One of the most vexing problems in historiography is dating an event when the usual sources offer conflicting chronologies of the event.Historians whould attempt to minimize the number of competing sources ,perhaps by eliminating the less credible ones .Once this is achieved and several sources are left,as often happens , historians may try ,though on occasion unsuccessfully,to determine independently of the usual sources which date is more likely to be right.

Which one of the following inferences is most strongly supported by the information above?

a)We have no plausible chronology of most of the events for which attempts have been made by historians to determine the right date.

b)Some of the events for which there are conflicting chronologies abd for which attempts have been made by historians to determine the right date cannot be dated reliably by historians
This hold out for me.
I would like to put my money on this one.

c)Attaching a reliable date to any event requires determining which of several conflicting chronologies is most likely to be true
I think this does not go with the passage because passage says often unsuccessfully So we can't be sure even after we find the best chronology from the group of chronology that we are dating an event successfully.
This option could be true but it said in must be true questions could be true options are good to disguise you but they are not the correct answers.

d)Determining independently of the usual sources which of several conflicting chronologies is more likely to be right is an ineffective way of dating events

e)The soundest approach to dating an event for which the usual sources give conflicting chronologies is to undermine the credibility of as many of these sources as possible.

What's the official Answer?

IMO B.

C i feel is wrong because it talks about 'dating any event' which is very universal. which should be avoided in GMAT.

OA plz..

the OA is B.However,i dont agree with it because i dont feel the stimulus contains enough info for us to conclude that the right date cannot be dated reliably by historians .The stimulus tells us that the historians can use two methods to get the exact date.It does not say that the two methods mentioned are the only methods existing in the world