Option 1: (A) - (II), (B) - (IV), (C) - (I), (D) - (III) -> Average Propensity to Consume (APC) = C/Y represents consumption per unit of income. Marginal Propensity to Consume (MPC) = ΔC/ΔY represents change in consumption per unit change in income. Average Propensity to Save (APS) = S/Y represents savings per unit of income. Marginal Propensity to Save (MPS) = ΔS/ΔY represents change in savings per unit change in income. The terms 'Average' refer to ratios (per unit), while 'Marginal' terms refer to rates of change (change per unit change). -> correct