Step 1: Establish logical pairings between items.
- (A) Correlation between variable input and output → Total Product (IV).
- (B) Production yielded per unit of variable input → Average Product (I).
- (C) Output alteration per unit of input modification → Marginal Product (II).
- (D) The trend of marginal product increasing initially, then decreasing as input escalates → Law of Variable Proportions (III).
Step 2: Confirm against provided choices.
The established pairings correspond to option (1).
Final Answer: \[\boxed{(A) – (IV), \; (B) – (I), \; (C) – (II), \; (D) – (III)}\]