This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth, Development, and Behavior, Subject name: Pediatrics
A child is brought to your clinic for a routine examination. She can put on a T-shirt but requires a bit of help dressing otherwise. She can copy a circle well but has difficulty in copying a square. Her speech is understandable and she knows four colors. She balances proudly on each foot for 2 seconds but is unable to hold the stance for 5 seconds. Which of the following is the most likely age of this child? 
Select and explain. 
A. 1 year, B. 2 years, C. 3 years, D. 4 years
A: 1 year
Answer: A: 1 year 
Explanation: Four- and five-year-old children should be able to copy a square and a cross; children younger than this age have difficulty with this task. By 4 years of age, their language should be fully understandable by the examiner. Children begin to be able to name four colors, define five words, and know three adjectives. A 4-year-old child can stand on each leg for 2 seconds, and by 5 years of age that skill can be maintained for at least 5 seconds. A 4-year-old child may require some help with some clothing, but by 5 years of age they are able to dress themselves independently, skip, and ask questions about word meaning.