What Would Be Required for an Unconformity to Trap Oil

Question 19
Multiple Choice

What would be required for an unconformity to trap oil at depth? A)permeable units above the unconformity and impermeable units below the unconformity B)permeable units below the unconformity and impermeable units above the unconformity C)permeable units above and below the unconformity D)impermeable units above and below the unconformity E)any of these