A. Comparing team performance often leads to unhealthy behaviors. Instead, focus on identifying and eliminating impediments that hinder team performance.

B. The one with the highest velocity is performing the best.

C. You need to normalize the estimates across the Scrum Teams and, based on that, create a balanced scorecard.

D. You need to look at several trends of different measures such as velocity, defects, and technical debt to get a picture of how the team is performing.