Final answer:
Democritus proposed that atoms were unchangeable, indestructible, and always existed, making 'all of the above' the correct answer to the student's question about the teachings of Democritus regarding atoms.
Step-by-step explanation:
The question refers to the ancient Greek philosopher Democritus, who taught that all material things are made up of atoms. According to Democritus' theory, atoms were unchangeable, , and always existed. Therefore, the correct answer to the question would be d) all of the above.
Democritus' concept of atoms laid the foundation for our modern understanding of atomic theory, though it would take nearly two millennia before his ideas were broadly accepted by the scientific community. His assertion that atoms were indivisible units that made up all matter was a revolutionary thought at the time, which contrasted with the more widely accepted ideas from philosophers like Aristotle, who believed that everything was composed of four elements: earth, air, fire, and water.