With consumption exponentially on the vertical access and disposable income on the horizontal axis, the consumption function intersects the 45° line at 8 trillion. This result indicates that ________.
1) consumption spending is less than 8 trillion because taxes must be paid
2) autonomous consumption is 8 trillion
3) consumption spending is more than 1 trillion because taxes have been paid
4) consumption spending is 8 trillion when disposable income is 8 trillion