"You're Melcome"

Andy: "Mank You."
Adam Quark: "You mean 'thank you.'"
Andy: "You're melcome."

While not the funniest of all the scifi sitcoms (which is a very short list), Quark did have the pedigree of having Buck Henry behind the show and Richard Benjamin in front of the camera.

A spoof of Science Fiction films and television series, "Quark" chronicled the adventures of Adam Quark, captain of a United Galactic Sanitation Patrol ship. His cohorts included Gene/Jean, a "transmute" with male and female characteristics; a Vegeton (a highly-evolved plant-man) named Ficus; Andy the Android and Betty and Betty (who were always arguing over who was the clone of the other). Based at Space Station Perma One were Otto Palindrome and The Head. Though Quark was supposed to stick to his sanitization patrols, he and his crew often met adventure with such colorful space denizens as the evil High Gorgon (the Gorgons were the villains), Zoltar the Magnificent, and Zargon the Malevolent.

As further proof of the wonder of the interweb you can see all the episodes on this great Quark fansite.