Final answer:
Option D, 'he is more scared of monsters than before,' does not indicate a child has entered the concrete operational stage of cognitive development. In this stage, children develop more realistic views and logical thinking skills, overcoming earlier fears like imaginary monsters.
Step-by-step explanation:
The question is identifying which scenario does not indicate that a boy has entered the concrete operational stage of development. The correct answer is Option D: 'he is more scared of monsters than before.' During the concrete operational stage, cognitive skills are more developed, and children begin to think more logically and realistically. They will have outgrown earlier fears like monsters and are less engaged in fantasy play. They can understand and perform operations like addition and subtraction, realize that people come back after they leave, can stay home alone for short periods, and can enjoy rule-based games such as checkers since their cognitive abilities allow them to understand and follow complex instructions.
According to Jean Piaget, between the ages of 7 to 11, children in this stage no longer fear the monster under the bed as they have a more realistic view of life. They are now capable of understanding that fictional characters and scenarios from storybooks or pretend play aren't real. Thus, an increased fear of monsters would be unusual for a child in the concrete operational stage.