PS DS

I would go with on this.

Do you know what the correct answer is??

I think in order to answer this question we need to know

who is the largest contributor and who is the smallest contributor...and the contribution of country x

both statements individually or together dont answer this question.

E is the right answer

67.8% -> 6 highest
Balance -> 153 countries
X -> one of 6?

1. 56% -> 4 highest. Each > X
Remainder 67.8 - 56 = 11.8 paid by other two in the group of 6.
INSUFFICIENT.

2. X = 4.8%
INSUFFICIENT.

Together, 11.8% paid by lowest 2 in the group of 6. Let these two be M and N.
If M = 5.9 and N = 5.9, X doesn't belong to the group of 6.
If M = 3.8 and N = 8, then M doesn't belong to group and X does.

So, answer is E.