Which of the following is a property of a substance?

The property of a substance refers to a characteristic that can describe its physical or chemical nature. Color is a direct observation of a substance that helps identify it and differentiate it from other materials. It is a fundamental property that can affect how a substance interacts with light and can have implications for its use and functionality in various contexts.

In contrast, time, distance, and speed are measurements or quantities that describe interactions or changes, rather than intrinsic characteristics of a substance. Time measures duration, distance measures space, and speed describes how fast an object is moving. None of these describe inherent qualities of a material itself, which is why color is the correct choice as a property of a substance.