The answer was 3 I think, referring to rock paper scissors balance relationships in RTS games, and fighting games, but it was Zynga in 2011 so they were mostly thinking about casual strategy. I think I said 1 at first because the question was kind of silly and I trend toward reductive answers with silly questions.
response to your edit: Your interpretation of the question makes a little more sense. He was talking about a specific number, not a concept\variable that is common in games. For Zynga I'd probably say energy or money or something, although any tracked resource that determines loss, victory or progression would work for your version.