The two different types of budgetary expenses in the federal budget are A state and local
B. valid and invalid
C mandatory and discretionary
D. appropriated and discretionary
Please select the bent anwer from the choices provided

In terms of the "great wheel of science", statistics are central to the research process (a) only between the hypothesis phase and the observation phase (b) only between the observation phase and the empirical generalization phase (c) only between the theory phase and the hypothesis phase (d) only between the empirical generalization phase and the theory phase