The correct answer is:
D. allows researchers to use their prior knowledge about the population.
A judgmental (or expert) sample relies on the expertise and judgment of the researcher to select participants who are most likely to provide valuable insights relevant to the study. This approach can leverage the researcher's existing knowledge about the population being studied. However, it does not guarantee a representative sample (contrary to option E), as it may introduce bias (contrary to option A) and may not involve uninformed respondents (contrary to option B) or a quota matrix (contrary to option C).