 Would the narrator consider his trip worthwhile?
Stuff like this: Want to visit Earth—see the Galaxy's most glittering and exclusive world? It's the best of its kind, the only really decent place where Earthmen can get a gander at the other species of the universe. "I'll be placed on exhibition at your Institute on Earth. I passed him along to Auchinleck to sign at anything short of top rate. It was the isolationism of the late 29th century that turned me into the successful proprietor of Corrigan's Institute, after some years as an impoverished carnival man in the Betelgeuse system. Before then, anyone could visit Earth. Every alien wants to see Earth once in his lifetime, and there's only one way he can do it.
 All of the above
 No - it was more trouble than it was worth  All of the above  No - it nearly cost him his life  Yes - he found many new non-terrestrials