What best defined Nirvana's impact from Nevermind through 1994?

Grunge Breakthrough Era (1991-1994) poll options

Grunge Breakthrough Era (1991-1994)

Nirvana: Nevermind to Kurt Cobain's Death Era (1991-1994)

Nirvana

• They brought grunge to the mainstream
• Kurt's lyrics captured a generation
• Their raw sound changed rock forever
• Their fame exposed the cost of stardom