Final answer:
The correct pairing is '1) Concrete operational; understands reversible relationships.' This stage allows children to logically think about concrete events, numbers, mathematical operations, and conservation.
Step-by-step explanation:
The correct pairing of a stage of cognitive development with the relevant ability to complete a task is: 1) Concrete operational; understands reversible relationships. During this stage (approximately 7 to 11 years old), children can think logically about real, concrete events. They grasp the use of numbers, can perform mathematical operations, and understand the concept of conservation. They recognize that actions like addition and subtraction, or multiplication and division, are reversible.
Option 2 is incorrect because children in the preoperational stage (approximately 2 to 7 years old) struggle with organizing objects based on size due to their limited logic and inability to perform concrete operations such as understanding conservation.
Option 3 is incorrect as it incorrectly states that children in the formal operational stage (from about age 11 and up) are limited to concrete thinking, whereas in reality, they are capable of abstract thought and handling hypothetical situations.
Option 4 is incorrect because during the sensorimotor stage (from birth through age 2), children do not have the capacity to understand the perspectives of others, as they are learning about the world through their senses and motor behavior.