In the Simple Macro Model,desired Investment Is Assumed to Be

Multiple Choice

In the simple macro model,desired investment is assumed to be autonomous with respect to national income.Which of the following will cause a shift of the investment function?
1) a decrease in interest rates
2) an increase in firms' optimism about the economy
3) an expectation of a downturn in future economic activity

A) 1 and 2
B) 2 and 3
C) 1 and 3
D) 1,2,and 3
E) 1 only