A oil and natural gas are seldom extracted from the same wells.
B oil and natural gas produced from the same well have their prices often determined by government decisions.
C oil and natural gas extracted from the same wells bring as an effect an indirect link between their prices.
D oil and natural gas prices have been increasingly independent in recent years because they are often produced from the same well.
E oil and natural gas prices have been increasingly dependent in recent years because they are often produced from the same well.