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
All of the following are genetic motor neuron diseases affecting predominantly lower motor neurons except 
Select and explain. 
A. Spinal muscular atrophy, B. Sandhoff's disease, C. Adult tay sachs disease, D. Adrenoleukodystrophy
D: Adrenoleukodystrophy
Answer: D: Adrenoleukodystrophy 
Explanation: Spinal muscular atrophy, Sandhoff's disease, Adult tay sachs disease are genetic motor neuron disease affecting lower motor neurons. Adrenoleukodystrophy is a genetic motor neuron disease affecting upper motor neurons. Ref Harrison 20th edition page 3144 , table 429-3