Why was the computer's move different?

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Avatar of kwkingdom123

This is a game between me and the computer. In here, I played 1. rxd8, and after rxd8, 2. kf5. However, when I analyzed this position using a computer, it suggested Bc4. After that, I tried to see what would happen after 2. kf5 by having the computer play itself. At the end, the advantage for white became a lot larger than Bc4. Why is that?