This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
Which one of the following is a rickettsial disease 
Select and explain. 
A. Weils disease, B. Rocky mountain fever, C. Relapsing fever, D. Pontaic fever
B: Rocky mountain fever
Answer: B: Rocky mountain fever 
Explanation: Rocky mountain spotted fever is caused by R.ricketsii.vector is dermacentar andersonii it is prevalent in noh america and South America. It is the most serious type of spotted fever Ref: AnanthNarayan and paniker's 10th edition