Which of the Following Is TRUE

Which of the following is TRUE?

A) Although officials at lower levels of bureaucracy are ensured job security by legislation, those at the middle and upper levels serve only so long as their bosses have confidence in them.
B) The bulk of the federal bureaucracy work in Mexico City.
C) The size of the federal bureaucracy is roughly equal to the size of the bureaucracies of state and local governments.
D) Officials at the lower levels of bureaucracy are unionized.
E) All of the above are true statements.