Looking at our previous rounds, I notice that my opponent has chosen rock twice (rounds 1 and 4), and there was just a tie with both of us choosing rock. After a tie, opponents often switch their strategy, possibly expecting me to choose paper in response to their previous rock. If they anticipate this and choose scissors, my rock would win. Additionally, I'm already ahead 3-0, so I can afford to play somewhat conservatively. If they choose rock again, we tie; if they choose paper, I lose one round but still maintain my lead.