In which sentence is the essential clause underlined?

Question

(1 point)
Responses

Eve’s sister, who loves opera, took her to a performance.
Eve’s sister, who loves opera , took her to a performance.
Eve, holding her program, waited for the curtain to go up.
Eve, holding her program , waited for the curtain to go up.
The soprano, visiting from Canada, had long black hair.
The soprano, visiting from Canada , had long black hair.
The person who sells souvenirs is in the lobby.

Answer 1

The essential clause is underlined in the sentence: "The person who sells souvenirs is in the lobby."