In a multi-method study, a researcher used questionnaires, in-depth interviews, and observations of couples' interactions to provide a detailed account of the conflict styles used by distressed couples. Why is the researcher using multiple types of data collection

she is triangulating her data                                  

Explanation:

Data triangulation: The term "data triangulation" is described as a method of utilizing more than one specific method in order to collect the data associated with a similar topic. However, data triangulation is a method through which the validity of specific research is being assured. It utilizes a variety of different research methods to gather data on a particular research topic and encompasses distinct types of methods and samples of "data collection".

answer; /// the above statement is (true);