Suppose in the United States consumption is described by the formula: C= $50 billion+0.9 Yd, where Yd is disposable income. If taxes are $100 billion and household income is $1,000 billion, what is the amount of household savings in the economy?
A. $50 billion
B. $950 billion
C. $900 billion
D. $40 billion
E. $860 billion