Final answer:
Exploratory research is the method used to broadly explore a topic to discover scope, focus, and other aspects, which helps in defining the research problem more clearly.
Step-by-step explanation:
The method that allows you to explore your broad topic and find out how much has been written about it, thus helping you discover what areas you may want to focus on, learn about other aspects of your topic, and more, is c) Exploratory research. Exploratory research is utilized when a problem is not clearly defined. It helps in identifying the scope of a problem and often involves seeking new insights, asking questions, and assessing phenomena in a new light. Different research methods like surveys, ethnographic field research, and historical secondary data analysis are chosen based on the research question and the study's objectives. Exploratory research, often considered interpretive research, is more descriptive and provides a solid ground for more conclusive later research. It allows the researcher to be flexible and to adapt the research method as new insights are gained.