The correct answer is - A) environmental changes decreased the production of food.
During its existence, Rome, did not faced any major challenges from environmental aspect that would reduce the food supplies to a point where it will make a big problem in the country. In times when there were some minor food problems, Rome was just using the food produced in the territories it had under its control, so it was never a major problem during its existence.
Index fossils, intrustions and cross-cutting relationships.
Explanation:
The correct list of three different geologic features that help scientists determine the relative ages of rocks by their position is "index fossils, intrusions, and cross-cutting relationships".
