Final answer:
Moral imperatives are based on universal ethical principles, social conventions are culturally specific rules that guide everyday interactions, and matters of personal choice are individual preferences without moral implications. Preschoolers, who are in the conventional stage of moral development, have a limited understanding of these concepts, while a fuller understanding develops during teen years and adulthood.
Step-by-step explanation:
Moral imperatives, social conventions, and matters of personal choice are different types of rules that guide our behavior. Moral imperatives are based on moral or ethical principles that are seen as universally applicable, such as the belief that one should not harm others. Social conventions are rules that govern everyday interactions within a society and often vary by culture, like dress codes or etiquette. Matters of personal choice are decisions that are left to the individual, like choosing a hobby or style of clothing, and typically do not have a moral or ethical dimension.
Concerning children's understanding, during the pre-conventional stage of moral development, preschoolers primarily experience the world through their senses and have a limited understanding of these different types of rules. As they grow and develop into the conventional stage, usually around the teen years, they become more aware of social conventions and moral imperatives. A complete understanding of these concepts, including the discrepancies between legality and morality, usually occurs in the post-conventional stage, which many people reach in adulthood.