What Is the First Stage in a Systematic,qualitative,comparative Historical Study

Multiple Choice

What is the first stage in a systematic,qualitative,comparative historical study?

A) select cases (such as nations) that vary in terms of the key concepts or events
B) specify a theoretical framework and identify key concepts or events that should be examined to explain a phenomenon
C) propose a causal explanation for the historical outcome and check it against the features of each case
D) identify similarities and differences between the cases in these key concepts or events and the outcome to be explained