This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
A 15 year old boy presents to you with history of fever, altered sensorium and purpuric rash for two days. On examination, the patient is found stuporous. He has a BP of 90/60 mmHg and extensive palpable purpura over the legs. Which of he following would be the most appropriate initial choice of antibiotic 
Select and explain. 
A. Vancomycin, B. Pencilline G, C. Ciprofloxacin, D. Gentamicin
B: Pencilline G
Answer: B: Pencilline G 
Explanation: None