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: Surgery
Which of the following is fibrosing type of thyroiditis? 
Select and explain. 
A. Hashimoto's thyroiditis, B. Riedel's thyroiditis, C. De Quervain's thyroiditis, D. All of the above
B: Riedel's thyroiditis
Answer: B: Riedel's thyroiditis 
Explanation: None