Final answer:
The students, who are able to use deductive reasoning and think abstractly, are in the formal operational stage according to Piaget. This stage begins around age 11 and marks the development of advanced cognitive skills such as the ability to handle hypothetical situations and engage in logical problem-solving.
Step-by-step explanation:
Based on the observations that the students can use deductive reasoning and think in abstract ways, it can be derived that according to Piaget, they are most likely in the formal operational stage of development. This is the final stage in Piaget's theory of cognitive development, which generally starts from around age 11 onwards. In the formal operational stage, children and adolescents have the capability to think about abstract concepts and hypothetical situations, enabling them to solve complex problems through logical reasoning. This stage encompasses abilities such as considering multiple points of view, imagining hypothetical scenarios, and engaging in high-level problem-solving and debate.
While previous stages, such as the concrete operational stage (approximately 7 to 11 years old), provide children with the ability to think logically about concrete events, the formal operational stage broadens their cognitive skills to include abstract and theoretical reasoning. It is a time where adolescents develop the skills necessary to reason logically, plan, and solve hypothetical problems, reflecting a significant leap in cognitive abilities.
The ability to engage in formal operational thought continues to mature throughout adolescence into adulthood. Although there have been proposals for a fifth stage of cognitive development, known as postformal thought, the question specifically asks about Piaget's stages, making the formal operational stage the most accurate answer (Option C).