Answer:
C. matter
Step-by-step explanation:
When hydrogen atoms collide at very high speeds, the natural electrostatic repulsion that exists between the positive charges of their nuclei is overcome and the atoms fuse, this fusion of light hydrogen atoms produces a heavier element, helium.
In short, nuclear fusion is a process by which nuclear reactions between light elements form heavier elements (up to iron), therefore fusion produces new types of matter.
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