A nоnprоfit оrgаnizаtion is lаunching a campaign to promote mental health awareness among young adults aged 18–30 in a metropolitan area. To prepare for the campaign, the organization wants to conduct a study of the target population to gather their insights on mental health attitudes. Due to limited budget, however, the organization can only gather data from a small community within the city. But they aim to ensure the sample reflects the population's diversity in gender and socioeconomic status. To achieve this, the team sets demographic criteria: 50% male, 50% female; 40% low-income, 40% middle-income, and 20% high-income. Participants are selected from a small community without randomization to meet these percentages. Which the following best represents the sampling method used in this scenario?