ETS (the GRE test-maker) doesn't license their questions, so no one is allowed to publish official GRE questions (other than ETS). That said, this would be a valid question to see on test day.
As far as difficulty levels go, GRE questions range from super easy to super hard. This particular question is in the 130-149 range.
QC Strategies
When you encounter a Quantitative Comparison question, be sure to consider which strategy might best apply:
Comment on Big Exponents
Is this problem is a Real GRE
ETS (the GRE test-maker)
ETS (the GRE test-maker) doesn't license their questions, so no one is allowed to publish official GRE questions (other than ETS). That said, this would be a valid question to see on test day.
As far as difficulty levels go, GRE questions range from super easy to super hard. This particular question is in the 130-149 range.