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: Medicine
Frenkel's exercise is done in case of- 
Select and explain. 
A. MND, B. Myopathy, C. Syringomyelia, D. Tabes dorsalis
D: Tabes dorsalis
Answer: D: Tabes dorsalis 
Explanation: None