You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For consistency, answers should be in all lower cased letters.

Category: ON THE COVER OF ROLLING STONE 
Clue: "Nothing Compares" to this singer seen on covers in 1990 & '91, & with even less hair in '92
sinead o\'connor

Category: SONGS OF THE '60S 
Clue: Louis Armstrong's only No. 1 hit, it hit the charts for 19 weeks in 1964
"hello, dolly!"

Category: FASHION 
Clue: This pattern of numerous round spots was first used on 19th c. fashion wear & named for a Bohemian dance

polka dot