This material _______________is composed of cement powder, aggregate, and water. It was first invented by the ____________. Now-a-days we mostly add steel rods to it and it is called ______________ .
a. Cement, The French architects, In-situ cement
b. Cement, The Romans, Pre-cast brick
c. Concrete, the Romans, Reinforced concrete
d. Concrete, The Americans, Reinforced concrete
