This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Medicine
Dissociated sensory loss is seen in 
Select and explain. 
A. Syringomyelia, B. Vitamin B12 deficiency, C. Transverse myelitis, D. Pellagra
A: Syringomyelia
Answer: A: Syringomyelia 
Explanation: Harrison's principles of internal medicine 17th edition. * The classical presentation in syringomyelia is a central cord syndrome consisting of a dissociated sensory loss and areflexic weakness in upper limbs