Which among the following are the forms of realism in the context of research?

Empirical realism and critical realism are the two forms of realism in research.

Empirical realism treats reality as knowable directly through the senses.

Critical realism separates the real world from our fallible knowledge of it.

Semiotics is the study of signs and meaning, not a form of realism.

Ordinal refers to a level of measurement, unrelated to realism.

Critical realism underpins much explanatory work in social science.