In constructing a self-driving robotic car, engineers face the challenge of designing a car that avoids common traffic problems like crashes and congestion. These problems can also affect fish traveling together in schools. However, the principles fish use to navigate in schools ensure that these problems are much less common within schools of fish than among cars on the road. Hence, __. Which one of the following most logically completes the argument? ['the best drivers use the same navigational principles that fish use in schools', 'a self-driving robotic car using the navigational principles that fish use in schools would be better than a human-driven car at avoiding crashes and congestion', 'studying the principles fish use to navigate in schools could help engineers to design a self-driving robotic car that avoids common traffic problems', 'constructing a self-driving robotic car requires expertise in fish biology']