____ IN LARGE QUANTITIES IN THE MIDDLE EAST, OIL BECAME KNOWN AS B...

21. - DE KIEM TRA MENH DE QUAN HE
DE KIEM TRA MENH DE QUAN HE
21. ____ in large quantities in the Middle East, oil became known as black gold because of the large profit itbrought.A. Discovering B. Discovered C. Which was discovered D. That when discovered