What type of relationship signifies that as one variable increases, the other decreases?

An inverse relationship is defined as a relationship where one variable increases while the other variable decreases. This type of relationship suggests that the two variables are connected in such a way that they move in opposite directions. For instance, in certain contexts such as in physics or economics, if the amount of one resource increases, the available amount of another related resource may decrease.

In contrast, a direct relationship indicates that both variables move in the same direction; as one increases, the other also increases. Proportional relationships maintain a constant ratio between two variables, suggesting that changes in one variable consistently produce predictable changes in the other. Lastly, a linear relationship refers to a relationship that can be represented by a straight line on a graph, which may be either direct or inverse but does not specify the direction of change. Thus, the defining characteristic of an inverse relationship is its opposition of variable movement, making it the correct choice.