How is a positive correlation characterized?

A positive correlation is characterized by the relationship in which, as one variable increases, the other variable also increases. This means that both variables move in the same direction. For example, if we consider the relationship between hours of study and test scores, typically, as the number of hours of study increases, test scores also tend to increase, illustrating a positive correlation.

The option that states that as one variable increases, the other decreases does not align with the definition of a positive correlation; rather, it describes a negative correlation. Similarly, stating that one variable remains constant while the other increases indicates no relational change, which contradicts the idea of correlation. Lastly, the mention of both variables showing no relationship describes the absence of correlation altogether, rather than a positive correlation. Thus, the option that highlights that both variables increase together captures the essence of a positive correlation effectively.