Scooby-Doo and Scrappy-Doo (1979)

S2E1 A Close Encounter with a Strange Kind

Scooby, Shaggy, and Scrappy find themselves abducted by aliens eager to study Earth's creatures. As the trio fumbles through their escape attempts, their hilarious misadventures lead the aliens to rethink their decision, concluding that Earth’s inhabitants are not as fascinating as they initially believed.