Let E = k^2+k-2 = (k-1)(k+2)
for E>0 means k-1 and k+2 have to be of same sign...ie either both positive or both negative.
Case 1. Both k-1 and k+2 are positive
k-1>0 , or k>1
k+2>0 or K<-2
Case 2. Both k-1 and k+2 are negative
k-1<0 , or k<1
k+2<0 or K>-2
Now look at the question stem.
If E>0 , we need more info.......so A is insufficient.
If E>0 , we need more info.......so B is insufficient.
taking both A and B , it boils down to Case 2.
Therefore answer is C.
I'm crossing the bridge.........