Research is a systematic inquiry towards understanding a complex social phenomenon or a process. Based on the research problem, the selection of research methods by the researcher may vary. A university teacher wants to study the relationship between socioeconomic status (SES) and achievement motivation of graduates enrolled in computer science. The ex-post facto research method will be appropriate to be used in this context. Ex post facto study or after-the-fact research is a category of research design in which the investigation starts after the fact has occurred without interference from the researcher. The researcher tries to understand the causal effects behind a phenomenon. The research basically focuses on how and what reasons have led that phenomena to occur. With the help of ex-post-facto research, the researcher tries to analyze the cause and effect phenomena of an event, action, or behaviour. In the above example, the university teacher will be able to find a link between socioeconomic status and achievement motivation of graduates only after analyzing student's attitudes after they have enrolled in computer science. Thus, option 2 is the correct answer. Additional Information: Experimental Research Method: Experimental research is research conducted with a scientific approach using two sets of variables. The first set acts as a constant, which you use to measure the differences of the second set. Quantitative research methods, for example, are experimental. Descriptive Research Method: Descriptive research is defined as a research method that describes the characteristics of the population or phenomenon studied. This methodology focuses more on the “what” of the research subject than the “why” of the research subject. Participant Observation Based Method: The participant observation method, also known as ethnographic research, is when a sociologist actually becomes a part of the group they are studying in order to collect data and understand a social phenomenon or problem. During participant observation, the researcher works to play two separate roles at the same time: subjective participant and objective observer.