Which of the following statements is correct? a. real gross domestic product, employment, and inflation change during a business cycle. all three tend to rise during an upturn and fall during a downturn. b. real gross domestic product, employment, and inflation change during a business cycle. real gross domestic product and inflation tend to rise during an upturn and fall during a downturn, but employment tends to fall during an upturn and rise during a downturn. c. real gross domestic product and employment, and inflation change during a business cycle. real gross domestic product and employment tend to rise during an upturn and fall during a downturn, but inflation tends to fall during an upturn and rise during a downturn.