Solon.
Solon didn't exactly establish rule by assembly (Ecclesia) -- it already existed. However, the assembly was controlled by the upper classes. Solon allowed all the male citizens, including those belonging to the lowest class, to be a part of the ruling assembly.
The court (Heliaia) also already existed, but Solon enabled the men from the lower classes to sit as jurors.
B) Solon
Hope This Helps ^_^
The correct answer is B. Solon, who implemented reforms that expanded participation in the Athenian assembly and established juries made up of citizens, thereby laying the foundations for Athenian democracy. His reforms were crucial in addressing social inequalities and allowed more citizens to engage in governance.
;