All of the following can lead to trophic ulcers in the fingers EXCEPT-

Answer is B (Subacute combined degeneration of cord): Subacute combined degeneration of cord (SACD) is associated with dysfunction of posterior column and coicospinal tract but spinothalamic tracts are preserved. Pain temperature and crude touch sensations remain intact in SACD because of the preservation of spinothalamic tract and hance trophic or neuropathic ulcers are not seen in SACD.