This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Virology, Subject name: Microbiology
Which of the following disease show centrifugal spread of rash 
Select and explain. 
A. Dengue, B. Small pox, C. Rocky mountain fever, D. Erythema multifotme
B: Small pox
Answer: B: Small pox 
Explanation: Description of rashes Deep seated All rashes in an area appeared in one stage, evolution was slow scentrifugal distribution - palm and sole and extensor surface were affected first. Fever subsided with appearance of rash. Ref: essentials of Medical microbiology apurba sastry 1st edition