If resources are allocated such that increasing one good's production requires decreasing another, this allocation is described as:

The situation described in the question reflects an efficient allocation of resources. When an economy is utilizing its resources to the fullest extent, it must face trade-offs; producing more of one good inherently means producing less of another due to limited resources. This fundamental concept is illustrated by the production possibilities frontier (PPF), which depicts the maximum feasible amount of two goods that can be produced with available resources.

An efficient allocation occurs when the economy is operating on the PPF, where all resources are being utilized effectively, and it is impossible to increase the production of one good without decreasing the production of another. Thus, the allocation is efficient because it maximizes the output given the available inputs.

In contrast, inefficiency would occur if the economy was operating inside the PPF, where it could produce more of one or both goods without any trade-off. Unproductive refers to an inability to attain economic goals, and suboptimal indicates that there could be a more favorable distribution of resources. Therefore, efficient is the most precise term to describe the allocation where increasing the production of one good necessitates the reduction of another.