In the Process of Analyzing Qualitative Data from Open Coding

In the process of analyzing qualitative data from open coding to axial coding in grounded theory research,which one of the descriptions below best describes the process of selecting a core category?

A) You select an important open coding category for the core category.
B) You identify the causal conditions and then determine an effect of it.
C) You list the categories and build on these by advancing an axial model.
D) You select a core category that best describes the process being studied.