<prompt> A 5-year-old child develops fever with rash on the first day of fever. Rash disappears after few days the child develops ataxia. Most probable diagnosis is:MeaslesFifth diseaseChicken poxRocky mountain spotted fever  <response>: Rash appearing on 1st day of fever suggests Chickenpox Ataxia can occur as a complication of varicella infection. 