I analyzed the opponent's moves from previous rounds: round 1: rock, round 2: paper, round 3: scissors, round 4: paper, round 5: scissors, round 6: rock, and round 7: paper. This suggests a possible repeating sequence: rock, paper, scissors, paper, scissors, rock, paper, ... which indicates that round 8 will likely be scissors. Since rock beats scissors, I choose rock for round 8.