Answer:
A. increase equilibrium income by $300 and cause the budget deficit to decrease by $90.
Explanation:
Change in income = Multiplier * Change in investment
Change in income = $3 * 100
Change in income = $300
So, Income tax increase by = $300 * 0.3
= $90. Government expenditure is unchanged. So, Budget deficit (G-T) decreases by $90.