4. Democritus called tiny fundamental particles of matter a. Protons b. Electrons c. Atomos d. Neutrons

c. AtomosDemocritus, a Greek philosopher who lived in the 5th century BC, theorized that all matter was composed of tiny, indivisible particles he called "atomos," which means "uncuttable" or "indivisible" in Greek. This is the root of our modern word "atom."