Arrange the following statement in the context of the effect of an autonomous change in aggregate demand on income and output.

(A) When autonomous investment increases, the aggregate demand shifts in parallel upwards.

(B) Equilibrium level of income depends on aggregate demand.

(C) Excess demand emerges in the economy.

(D) The output will be greater than the original output.

Choose the correct answer from the options given below:

Option 1 -> Sequence is (B), (A), (C), (D) - This follows the logical chain but places excess demand before output increase, which is chronologically accurate during adjustment.

Option 2 -> Sequence is (A), (B), (C), (D) - This starts with the investment increase before establishing the foundational relationship, making it less pedagogically sound.

Option 3 -> Sequence is (B), (A), (D), (C) - This establishes the foundation first, then shows the shock, followed by the outcome and adjustment process.

Option 4 -> Sequence is (C), (B), (D), (A) - This illogically starts with excess demand before any change occurs, making it incorrect.

Hence, Option 3: (B), (A), (D), (C) -> The correct sequence is: (B) First, we establish that equilibrium income depends on aggregate demand as the foundational concept. (A) Then, autonomous investment increases causing aggregate demand to shift upward in parallel. (D) This leads to output being greater than the original output through the multiplier effect. (C) Finally, excess demand emerges in the economy during the adjustment to the new equilibrium level. This sequence represents the complete causal chain of events from the theoretical foundation to the final market adjustment. -> correct