What type of philosophical assumption addresses the nature of reality?

The correct choice, which addresses the nature of reality, is grounded in metaphysical assumptions. Metaphysics is a branch of philosophy that explores fundamental questions about existence, the nature of reality, and the relationship between mind and matter. It seeks to understand concepts such as being, existence, and the universe as a whole.

In the context of philosophical inquiry, metaphysical assumptions help to establish a framework for understanding what is real versus what is merely perceived or believed. This is crucial in fields like social science, where researchers must consider the underlying realities they are investigating.

The other options pertain to different areas of philosophical thought. Epistemology deals with the nature and scope of knowledge—how we know what we know and the justification of beliefs. Ethical assumptions focus on moral principles and judgments about right and wrong, guiding behavior and decision-making. Pragmatism, on the other hand, emphasizes the practical application of ideas and theories in real-world situations, often considering the consequences of actions and beliefs rather than their metaphysical underpinnings. Each of these branches of philosophy serves a distinct purpose but does not specifically address the fundamental nature of reality as metaphysics does.