(high school sociology) the united states has an open class system based on social mobility that includes a. horizontal mobility. c. intergenerational mobility. b. vertical mobility. d. all of the above

D. all of the above

Explanation:

In open class system, every one has the chance to increase or decrease their social status since most Americans do not acknowledge things such as nobles blood or anything similar to that.

All of the options above are example of social class change that can occurs in open class system.

- Horizontal mobility,

Occurs when a person change their social status, but that change does not necessarily increase or reduce their social power.

-  inter generational mobility.

Occurs when social status change within the children due to the effort that made by their parents. (For example, their parents were poor. But somehow managed to work their way up and obtain wealth. When the children are born, they experience an increase in social status)

- Vertical mobility

Occurs when a person change their social status , but the change caused either an increase or decrease in their social power.

for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.

the answer your looking for is c. : )