Is one of these the most sampled sound of all time (in terms of then being incorporated into other released records), or is it something else? As samples should go through legal clearance, the information should be out there, somewhere...
This article says that the most sampled song of all-time is "Change the Beat" by Fab 5 Freddy:
According to the BBC, though, one song has proven particularly popular among DJs and musicians: "Change the Beat," by Fab 5 Freddy.
According to the site Who Sampled, "Change the Beat" has been featured in nearly 1,300 songs, including "Boyz-N-The-Hood" by Eazy-E and last year's "Thrift Shop", making it the most sampled song of all time.