This question is based on the following paragraph both hundred on the InColor made of the complex carbon-based molecules in both originated with living creatures of some kind. Both are a little sources of energy for the modern world and both were formed by geologic processes over millions of years. However, petroleum was mainly formed from the reins of ocean-dwelling microorganisms. Call, on the other hand, originated from a decade vegetation an agent swamped in Boggs. In any case, it took millions of years for both: oil to be produced. This is the case because it took that much time for overlying sediments to produce the Unimaginable heat and pressure that would one day allow us to harvest season energy resources. What is one clue word or phrase in the passage that indicates a contrast?