Answer: A) Solar
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Step-by-step explanation:
The sources of wind, hydro, and fossil fuels all use a turbine. So we can rule out choices B,C, and D.
A turbine is basically a wheel that spins to generate motion energy into electrical energy. Think of it like one of those stationary bicycles and the bike powers up a nearby lamp (the faster you pedal, the brighter the bulb gets). Another example that's similar to a turbine would be those flashlights where you can rotate a crank to have the light come on (which is useful for when the batteries are completely dead). The windmill blades act as a giant turbine that the wind spins around. Hydroelectric turbines are spun by the falling water. Fossil fuels are burned to create very hot steam which then powers a turbine. Even nuclear power uses turbines as well. With fossil fuels and nuclear energy, the idea is to heat up a vat of water and then turn that intensely hot steam into electrical energy through a turbine.
With solar panels however, the electrical energy is converted through a process of sunlight interacting with the solar cells that doesn't require a turbine. This explains why you can use solar panels to power up devices such as phones or laptops without having any moving parts. All you need is a flat set of solar panels.
There is a slight variation of solar power known as "concentrated solar power", aka "concentrated solar thermal", where solar panels are not used. Instead, a vast array of mirrors are set up to aim the suns rays at a very specific narrow area. Think of it like a magnifying glass to focus the suns rays. The place where the narrow beam hits has a very high temperature. This high temperature heats up water to turn to steam, and the process from here is effectively the same as fossil fuels or nuclear energy. So that means turbines are involved with concentrated solar power. I'm assuming your teacher is specifically referring to solar panels when they mentioned choice A.