The change in output per unit of change in the input when all other inputs are held constant, is termed as .

Option 1 -> Total Product refers to the total quantity of output produced, not the change in output.

Option 2 -> Marginal Product measures the change in output resulting from a one-unit change in input, keeping other inputs constant.

Option 3 -> Average Product is total output divided by the quantity of input used, not the change in output.

Option 4 -> Marginal Utility relates to consumer satisfaction from goods, not production output.

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Hence, Option 2: Marginal Product -> Marginal Product (MP) is defined as the additional output produced when one additional unit of a variable input is employed while keeping all other inputs constant. Mathematically, MP = ΔTP/ΔL (change in total product divided by change in labor or any input). For example, if hiring one more worker increases output from 100 to 115 units, the marginal product is 15 units. This concept is fundamental in production theory and helps firms determine optimal input levels. -> correct