A middle aged man presents with progressive atrophy and weakness of hands and forearms. On examination he is found to have slight spasticity of the legs, generalized hyper-reflexia and increased signal in the cortico-spinal tracts on T2 weighted MRI. The most likely diagnosis is -: (A) Multiple selerosis, (B) Amyotrophic latetal sclerosis, (C) Subacute combined degeneration, (D) Progressive spinal muscular atrophy
Answer is B. None