From an Overall Standpoint, Which Statement Is True

From an overall standpoint, which statement is true?

A) The Texas economy is closely tied to the national economy.
B) The Texas economy is largely immune to the national economy.
C) The Texas economy is much larger than the national economy.
D) The Texas budget cycle effectively insulates the state economy from the rest of the world.
E) Oil and natural gas production within the state's borders generate over two-thirds of state tax revenue.