Final answer:
The longest-aired 90s sitcom is 'Frasier,' which ran for 11 seasons from 1993 to 2004 and won multiple awards.
Step-by-step explanation:
The 90s sitcom that was aired the longest is Frasier, which successfully ran for 11 seasons. Frasier originally aired from 1993 to 2004 and it was a spin-off from the popular sitcom Cheers. Not only did it manage to capture a significant audience throughout its run, but it also won numerous awards, including Emmys for Outstanding Comedy Series.