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
Primary cartilaginous joint is called as: 
Select and explain. 
A. Symphyses., B. Synchondrosis., C. Syndesmosis., D. Synarthroses.
B: Synchondrosis.
Answer: B: Synchondrosis. 
Explanation: None