Option 2: (A) - (III), (B) - (I), (C) - (IV), (D) - (II) -> Let's understand the economic concepts:
(A) Marginal Propensity to Consume (MPC) = ΔC/ΔY = Change in consumption per unit change in income = (III). It measures how much additional consumption occurs when income increases by one unit.
(B) Marginal Propensity to Save (MPS) = ΔS/ΔY = Change in savings per unit change in income = (I). It measures how much additional savings occurs when income increases by one unit.
(C) Average Propensity to Consume (APC) = C/Y = Consumption per unit of income = (IV). It shows the proportion of total income that is consumed.
(D) Average Propensity to Save (APS) = S/Y = Savings per unit of income = (II). It shows the proportion of total income that is saved.
Note: MPC + MPS = 1 and APC + APS = 1 -> correct