7. The Bigdrillcompany drills for oil, which it sells for $200 million tothe Bigoil company to be made into gas. The Bigoilcompany's gasis sold for a total of $600 million. What is the total contribution tothe country's GDP from companies Bigdrill and Bigoil?(A) $200 million (B) $400 million(C) $600 million (D) $800 million