Which of the following responses most accurately completes the definition of a worker's "Marginal Revenue Product (MRP)"? The MRP represents the change in the:
A. Firm's Total Costs (TC) as the result of hiring an additonal worker.
B. Firm's Total Revenues (TR) as the result of hiring an additional worker.
C. Firm's profits as the result of hiring an additional worker.
D. Firm's output (q) as the result of hiring an additional worker.