Name at least one race on which Troi's empathic abilities are ineffective.
Jack London was primarily a 20th Century author (all his novels were written after 1901) and tafkats said "did the crew
befriend"... so I think he meant Mark Twain (Samuel Clemens). But you're partly right in that he befriended Data and wrote some short stories before 1901.
But to answer your question: the Breen (since we see her apparently "read" a Ferengi. Just covering my ass!)
Let's step this up a notch, shall we?
Name every episode in which we see a poker game aboard the Enterprise.
Bonus points: Name the episode in which a poker scene was written, but for whatever reason never made it into the final cut!