The correct answer is: oil, natural gas, groundwater.
An anticline is a fold in the Earth’s crust that is convex upward. Oil and natural gas are formed from the remains of ancient plants and animals that have been buried and subjected to heat and pressure over millions of years. These hydrocarbons are lighter than water, so they will naturally migrate upward through the Earth’s crust until they reach a trap. A trap is a geological structure that prevents the hydrocarbons from further migrating upward.
The most common type of trap is an anticline. In an anticline, the oil and natural gas will accumulate in the crest of the fold, while the groundwater will accumulate in the basin. This is because the oil and natural gas are lighter than water, so they will float on top of the groundwater.
The other options are incorrect because:
- Natural gas is lighter than oil, so it will accumulate on top of the oil.
- Groundwater is heavier than oil and natural gas, so it will accumulate at the bottom of the trap.
I hope this helps! Let me know if you have any other questions.