Explain simply why Kristen Joy Schaal is the correct answer to: Passage: Kristen Joy Schaal (/ l /; born January 24, 1978) is an American actress, voice actress, comedian and writer. She is best known for her roles of Mel in Flight of the Conchords, the over-sexed nurse Hurshe Heartshe on The Heart, She Holler, Louise Belcher in Bob's Burgers, Mabel Pines in Gravity Falls, and Carol in The Last Man on Earth.

Question: Based on this passage, who plays mabel's voice on gravity falls?. Explanation:
The important part for answering this question is: She is best known for her roles of Mel in Flight of the Conchords, the over-sexed nurse Hurshe Heartshe on The Heart, She Holler, Louise Belcher in Bob's Burgers, Mabel Pines in Gravity Falls, and Carol in The Last Man on Earth.