The energy which we obtain from the sun is called solar energy or radiant energy. The sun's energy is stored in coal, natural gas, water and wind. Coal, oil, and natural gas are known as fossil fuels.
Fossil fuels were formed over millions of years ago when the remains and fossils of prehistoric plants and animals sank to the bottom of swamps and oceans. These animal and plant remain were slowly covered and crushed by layers of rock, mud, sand, and water. The pressure of all those layers caused the plants and animals to break down and change into coal, oil and natural gas. We use the energy in these fossil fuels to make electricity. As of the year 2019, most of the energy we use comes from fossil fuels. However, fossil fuels are known as non-renewable sources of energy. They cannot be used over and over again. This means that one day they will run out!
_______ formed over millions of years ago from the remains of prehistoric plants and animals.

Options

A. Fossil fuels
B. Biogas
C. Water
D. Nuclear energy

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for what is formed over millions of years from the remains of prehistoric plants and animals.

2. **Identifying Key Terms**: The key terms in the question include "formed over millions of years," "remains," and "prehistoric plants and animals."

3. **Recalling Information from the Passage**: The passage states that fossil fuels were formed when the remains of prehistoric plants and animals sank to the bottom of swamps and oceans. They were then covered by layers of rock, mud, sand, and water, which created pressure that transformed them into coal, oil, and natural gas.

4. **Analyzing the Options**: The options provided are:
- a. Fossil fuels
- b. Biogas
- c. Water
- d. Nuclear Energy

5. **Selecting the Correct Answer**: Based on the information from the passage, fossil fuels (which include coal, oil, and natural gas) are indeed formed from the remains of prehistoric plants and animals. Therefore, the correct answer is:
- a. Fossil fuels

6. **Final Answer**: Fossil fuels formed over millions of years ago from the remains of prehistoric plants and animals.

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