Which of the following is a hallmark of the Concrete Operational Stage in Piaget?

• A. Hypothetical-deductive reasoning
• B. Conservations
• C. Abstract thinking
• D. Egocentrism

Answer: (B)

In Piaget's theory, the Concrete Operational Stage is marked by the emergence of logical thinking about concrete objects and events, with conservation being a central milestone. Conservation means understanding that quantities stay the same even when their appearance changes—for example, knowing that pouring water into a different-shaped container doesn’t alter the amount, or recognizing that spreading out a row of coins doesn’t create more of them. This shows children can perform mental operations on real objects, understand reversibility (you can mentally reverse a change), and consider multiple aspects of a problem at once (decentration).

Other options point to abilities that belong to later stages or different patterns of thinking. Hypothetical-deductive reasoning and abstract thinking are hallmarks of the Formal Operational Stage, when thinking becomes more abstract and systematic. Egocentrism is characteristic of the Preoperational Stage, when a child has difficulty seeing viewpoints other than their own. So conservation best captures the distinctive change of the Concrete Operational Stage.