The walls are thought to have been a symbolic show of authority, designed to preserve the privacy of royal families and set them apart from and above commoners. It is also important to note that the walls surrounded and later adjoined huts made of daga (mud and thatch), linked with them to form a series of courtyards.
The correct option is B.
The energy crisis of 1970 gave birth to energy reform in America. As a result of the crisis, efforts were made to stimulate domestic oil production, to reduce dependency on fossil fuels and to find alternative sources of power.
