Answer:
C. They use formal gestures when they greet each other
Step-by-step explanation:
Houyhnhnms are a fictional race of intelligent horses described in the last part of Jonathan Swift's satirical 1726 novel Gulliver's Travels.
Houyhnhnms live simple lives wholly devoted to reason. They speak clearly, they act justly, and they have simple laws. Each Houyhnhnm knows what is right and acts accordingly. They are untroubled by greed, politics, or lust. They live a life of cleanliness and exist in peace and serenity. They live by the grand maxim: Cultivate Reason and be totally governed by it. So perfect is their society, in fact, that they have no concept of a lie, and therefore no word to express it.