[Solved] Sampling is necessary because A)causality cannot be established at a single moment in time. B)a researcher cannot study every member of the population of interest. C)it reduces the number of variables at play in a situation. D)it focuses on one dimension of a complex social problem. Categories: Distinct groups or classes into which data or items can be divided based on shared characteristics or qualities. Chi-square: A statistical test used to compare observed frequencies with expected frequencies for categorical variables to assess the likelihood of an association. Parametric Statistics: A branch of statistics that assumes data comes from a type of distribution and makes inferences about the parameters of the distribution. Sample Size: The number of observations or data points used in a study or analysis.