C
Below is a question with multiple-choice answers. Choose the correct option based on your reasoning.

### Question:
Photovoltaic cells capture photons of sunlight and transform them directly into electricity. Many of Earth's other energy resources are simply transformed solar energy. Which two energy resources store energy that did not begin as solar energy?

### Choices:
A. oil and coal
B. wind and wood
C. nuclear and geothermal
D. hydropower and natural gas

### Answer:
