This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pediatrics
At what age child begins to use past and present tense 
Select and explain. 
A. 1 Years, B. 2 Years, C. 18 Months, D. 30 Months
D: 30 Months
Answer: D: 30 Months 
Explanation: Begin to identify objects from a group by their function and pas (ie. "which one has wheels", "which one can we eat") Begin to use verbs with "ing" endings (i.e. "eating"); Early concepts such as "big, little" are identified; Child will use "no, not" and answer "where" questions Reference: GHAI Essential pediatrics, 8th edition