Working out RICE scores

Using RICE = (Reach x Impact x Confidence) / Effort, which feature scores highest? Feature A: reach 2,000 users per quarter, impact 2, confidence 80%, effort 4 person-months. Feature B: reach 500, impact 3, confidence 100%, effort 1. Feature C: reach 6,000, impact 0.5, confidence 50%, effort 2.