I have two rosters derived from a multi-select question with “Others” as an option. One roster (called A) is derived from the selected options other than “Others”, the other roster (B) is derived from the list question that specify “Others”. In my case, the MCQ is “What infrastructure does your village have?” In the two rosters mentioned above, I asked the number of households each infrastructure serves (variable a1 in A and variable b1 in B). I want to choose the three infrastructures that serve the most households to ask for more details (in a new roster). How can I make it? Specifically, how can I select the three infrastructures from two rosters (A and B)? Can I merge these two rosters (A and B) into one? Since they share the same questions and the only difference is the type of their source questions.