Final answer:
Professor Merkel will likely use surveys to assess identity status in adolescents and emerging adults, as they collect a broad range of self-reported data efficiently.
Step-by-step explanation:
Professor Merkel, who focuses on identity development in adolescents and emerging adults, will most likely utilize surveys as a research method to assess identity status. Surveys are particularly useful for collecting self-reported information about thoughts, experiences, and beliefs from a larger sample in a relatively short amount of time, although the depth of data may not be as comprehensive as that from a case study. Other methods, like naturalistic observations, might not be as effective for directly assessing internal states of identity, while a meta-analysis would synthesize existing research rather than collecting new data. Considering the goal is to understand a broad aspect of developmental psychology, surveys provide a balance of scope and detail needed for Merkel's research.