Looking at the previous rounds, my opponent has chosen rock twice (rounds 1 and 4) and paper twice (rounds 2 and 3), but never scissors. There seems to be a possible pattern of alternating between rock and paper. However, it's also possible that my opponent might introduce scissors in this round to mix things up. By choosing rock, I would beat scissors if they finally play it, and tie if they repeat their rock choice from the previous round. While I risk losing to paper, I believe rock gives me the best strategic chance based on the opponent's previous moves.