An effective method to use in collecting information from a diverse population would be:

Collecting information from a diverse population requires a method that ensures representation across various demographic groups (e.g., age, race, income). Stratified sampling (option C) divides the population into subgroups (strata) based on key characteristics and then samples from each stratum, ensuring that all groups are proportionately represented. The APA’sAICP Certification Exam Content Outline(2022), under “Research and Assessment Methods,” defines stratified sampling as “a method that ensures representation of diverse subgroups by sampling proportionally from each stratum.” This is particularly effective for diverse populations compared to random sampling (A), which may miss smaller groups. Option B (mail-back questionnaires) often has low response rates among diverse groups due to language or access barriers. Option D (public meetings) may exclude those unable to attend due to time, transportation, or language issues. TheCPC Study Manual(2024) states, “Stratified sampling is the most effective method for collecting data from diverse populations, as it ensures proportional representation,” supporting option C.