How did the actions of gaius marius change the roman republic?

a: he angered the senate by proposing that rome divide public lands among the returning military and their families.
b: he replaced the elected consuls and the senate with an empire that could be inherited by members of the ruler's family.
c: he angered the senate by convincing men to serve in wars by promising them land and citizenship.
d: he restructured the city's politics and strengthened the senate's power.