Final answer:
Secondary research is the use of previous data to answer current questions, offering nonreactive analysis with validity and value neutrality critical to this approach.
Step-by-step explanation:
The correct option is secondary research, which is a category of marketing research best defined as the use of new interpretations of existing information collected to solve a problem at hand or answer current questions. Unlike primary research, secondary research involves analyzing data that has already been collected by others. This can include sources such as books, articles, or data from agencies like the World Health Organization (WHO), where the original collection methods do not interfere with or influence the behavior of the subjects, making it nonreactive or unobtrusive research.
Sociologists and researchers can contribute to knowledge by engaging in secondary data analysis, as seen in various sociological studies like Middletown by John S. Lynd and Helen Merrell Lynd, where surveys were a key method used. However, it's crucial to ensure the validity of the measures and the principle of value neutrality while conducting such analyses to prevent biases.