According to History,the Concept That All Matter Is Composed of Atoms

According to history,the concept that all matter is composed of atoms was first proposed by

A) the Greek philosopher Democritus,but not widely accepted until modern times.
B) Dalton,but not widely accepted until the work of Mendeleev.
C) Dalton,but not widely accepted until the work of Einstein.
D) Dalton,and widely accepted within a few decades.