We can cross of A. because if A. were to be correct, nothing else would be correct.
Now we know it has to be B. or C. and D.
D. has to be one of them since you can't have B. and C.
To find out if it is either B. or C. we need to think into it more. So if we had the mean of 80%, that means we need to have some scores over 75%. That would be C. since it says 75% or greater.
