As High-Tech Industry Came to Dominate Silicon Valley,it Encouraged Much

As high-tech industry came to dominate Silicon Valley,it encouraged much upward mobility.It also:

A) increased the cost of living,which hurt the middle class and the poor
B) decreased the cost of living by increasing economic opportunities
C) kept inequality level
D) increased the cost of entering technological markets,which minimized the growth of the wealthy
E) none of these choices