Answer:
The concrete operational stage.
Step-by-step explanation:
Piaget’s cognitive development theory is a type of comprehensive theory that check the human intelligence. This theory explains the ways by which the human acquire its intelligence.
The third stage of the cognitive theory is the concrete operational stage. This stage develops in the individual with 7 to 11 years of age. The individual is aware to known the use of logic in this stage. In this question the child is able to use its logic to tell the answer. Hence, he is in the concrete operational stage.
Thus, the correct answer is option (D).