I can't remember how they handle it in the show. In the books, they take it all. But, in the books, Missandei is only 10, so they aren't really a road map to the show anymore.
Can be a one or both but I thought they went with the "both" based on the "Let me see" dialogue. And linked articles says LOTS of people hit the Google on it last night.
http://www.huffingtonpost.ca/2017/07/24/game-of-thrones-eunuch-definition_a_23045444/