Which description best matches Democritus's idea of the atom?

Around 400 B. C. E., the Greek philosopher Democritus introduced the idea of the atom as the basic building block matter.

Around 400 B. C. E., the Greek philosopher Democritus introduced the idea of the atom as the basic building block matter.

Democritus thought that atoms are tiny, uncuttable, solid particles that are surrounded by empty space and constantly moving at random.