This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
A child is able to copy a cross at what age? 
Select and explain. 
A. 4 years, B. 5 years, C. 2 and half years, D. 3 years
A: 4 years
Answer: A: 4 years 
Explanation: None