According to Piaget's Cognitive Developmental Theory, one of the milestones of preoperational thought is the ability to:

• A. understand the concept of conservation
• B. solve hypothetical-deductive reasoning problems
• C. think logically about abstract concepts
• D. engage in symbolic play and use language to represent objects

Answer: (D)

Verified step by step guidance

1. Identify the stage of cognitive development being discussed, which is the preoperational stage according to Piaget's theory.
2. Recall the key characteristics of the preoperational stage, typically occurring between ages 2 and 7, such as symbolic thinking, egocentrism, and difficulty with conservation tasks.
3. Understand that conservation—the understanding that quantity remains the same despite changes in shape or appearance—is not yet mastered in this stage; it develops later in the concrete operational stage.
4. Recognize that hypothetical-deductive reasoning and logical thinking about abstract concepts emerge in the formal operational stage, which comes after the concrete operational stage.
5. Conclude that a major milestone of the preoperational stage is the ability to engage in symbolic play and use language to represent objects, reflecting the development of symbolic function.