After analyzing the previous rounds, I notice both of us have played each option once, with no clear pattern emerging yet. Since I just played rock in round 3 and won, my opponent might anticipate me continuing with rock or switching to paper (which would beat rock). If they expect me to play paper, they might choose scissors. Alternatively, they might play paper to counter my previous rock. Either way, scissors would be effective - beating paper or tying with scissors. This also avoids being too predictable by not repeating my previous move.