The OA is : B
Yes you are right that th equestion states to have different numbers also, it states a seven day week rather than a 6 day week.
I guess here it is that, how this is possible with B:
90-38=52. So 52 needs to be divided in 6 days.
Option 1: Friday 12(greater then 11)
gives 40 to be divided in 5 days, that makes an average of 8/day. It can be achieved by 6,7,8,9,10. Also it satisfies that Friday is second highest. If we take any other combination to make an average of 8 in 5 days, it will not give us Friday as the second highest.
Option 2: Friday 10(less then 12)
It gives us 42 to be divided in 5 days, that again makes out that any combination we try will not be able to make friday (10) as the second highest.
So, it is clear that Option 1 is true, so only B is sufficient. making that on Friday the number was greater then 11.....
With A: The picture is not clear about the highest number, so it can have N number of combinations and then Friday with second highest cane be greater then or less then 12....So not sufficient...
I hope now you are able to get the explanation right.....Hope it helps!!!
parallel_chase made some mistakes, but still managed to get the answer right, as the approach was correct and real good....thanks parallel_chase for making me understand the method.....