The principle of _________ describes how a change in a property affects the overall property value.

The principle of contribution is the correct choice because it directly relates to how an individual change or improvement made to a property affects its overall value. This principle states that the value of a property is influenced by the contribution of each component or feature to the overall value. For instance, if a homeowner adds a swimming pool, the increase in market value depends on how much value that pool adds compared to the total property value. Essentially, an enhancement will not necessarily yield a return proportional to the cost unless it aligns with buyer expectations and local market values.

Understanding the principle of contribution helps appraisers assess whether specific improvements enhance a property's value and to what extent. Each improvement is evaluated based on its contribution to the overall functionality and appeal of the property, guiding both appraisals and market expectations.