What describes a relationship where a change in one quantity produces the same change in another quantity?

A relationship where a change in one quantity produces the same change in another quantity is known as a direct proportion. This means that as one variable increases, the other variable also increases at a constant rate, and similarly, if one decreases, the other also decreases proportionally. In mathematical terms, this is often expressed as ( y = kx ), where ( k ) is a constant. This concept is crucial in various applications, especially in the electrical field, where voltage, current, and resistance can show direct proportional relationships, such as Ohm's Law.

In contrast, an inverse proportion describes a situation where an increase in one quantity results in a decrease in another. A linear relationship involves a linear equation which may represent direct or indirect relations, while a quadratic relationship involves a variable squared, leading to a parabolic graph that does not maintain constant rates of change. The clear nature of direct proportion is what distinctly sets it apart and makes the second option the right answer in this context.