Which term refers to a collection of assertions explaining variable relationships?

The term that refers to a collection of assertions explaining variable relationships is indeed theory. A theory provides a systematic framework that organizes and explains various phenomena, often encompassing multiple hypotheses and previous observations. By integrating these assertions, a theory helps to establish connections between variables, allowing for a deeper understanding of how they interact and influencing the development of further research.

A hypothesis, while related, is more specific and represents a testable prediction about the relationship between variables rather than a comprehensive framework. Correlation pertains specifically to the statistical relationship between two variables, without the broader context of explanation or assertion that a theory provides. Observation refers to the act of watching and recording events or behaviors, which can contribute to the development of theories but does not itself encompass a collection of explanations.