What is the author mostly focusing on in the firsthand account? A. safety data gathered by rovers that will help protect future astronauts who visit the Red Planet B. cost of exploration, benefits of exploration, and the use of robots and humans in studying Mars C. the use of robotics, such as the Curiosity rover, and the future of robotics in space exploration D. a comparison of federal expenses with the cost of the 2020 rover which will send humans to Mars