This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anatomy
All of the following statements about Diploic veins are true, except? 
Select and explain. 
A. Develop around 8th week of gestation, B. These have no valves (valveless), C. Present in cranial bones, D. Have a thin wall lined by a single layer of endothelium
A: Develop around 8th week of gestation
Answer: A: Develop around 8th week of gestation 
Explanation: Diploic veins develop after bih and are not visible before 3 years of life. They fully develop only by 15 years of age.