Final answer:
The answer to the question is b) Formal operations.
Mental actions that follow systematic, logical rules are referred to as formal operations, the fourth stage of Piaget's cognitive development theory, starting around age 11 and continuing into adulthood, enabling abstract and logical thinking.
Step-by-step explanation:
Mental actions that follow systematic, logical rules are known as formal operations. The term originates from the work of Swiss psychologist Jean Piaget, who identified formal operations as the fourth stage in his theory of cognitive development. This stage typically begins around age 11 and continues into adulthood.
At this stage, individuals are able to think abstractly, systematically, and logically. They are capable of performing mental operations using abstract concepts, and they can work through hypothetical situations. Piaget contrasted this stage with the concrete operational stage, which focuses on logical thinking but is limited to concrete, immediate experiences. Therefore, the answer to the question is b) Formal operations.