How were the Romans able to move from wooden houses to more permanent structures?

The correct answer to this open question is the following.

Although there are no options provided, we can say the following.

Romans were able to move from wooden houses to more permanent structures because they started to experiment with the use of concrete, cement, and better formulas to increase the quality of this material. Romans were also capable of exploring new ideas to create forms such as vaults and arches. Let's have in mind that Romans originally used a different material called "tufa" which was a volcanic rock. A solid material but not an aesthetical one. Years later, Romans cold mix concrete with volcanic sand to create a more resistant material. With the use of marble, Romans were capable of creating marvelous buildings and temples.

the ss was the main organization responsible for the genocidal murder of around six million people of european ethnic minorities, essentially jews, in the holocaust. the members of all its branches committed war crimes and crimes against humanity during the second world war (1939-1945). likewise, the ss were involved in commercial enterprises and exploited the inmates of the concentration camps as slave laborers.

the tortures and assassinations committed by the ss were the result of an ideology developed long before the armed conflict, this ideology was based on the racial supremacy of the germans over the rest.

the noble might have thought that the system was far because they had lot of things and riches and the serf would have thought that the feudal system was un fair because of the way they were treated.