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: Surgery
Which of the following organism is most commonly responsible for ascending cholangitis? 
Select and explain. 
A. E.coli, B. Streptococci, C. Pseudomonas, D. Anerobes
A: E.coli
Answer: A: E.coli 
Explanation: The commonest causative organism is E.coli. Though Klebsella, Pseudomonas, Enterococci etc also produce the condition. Charcot's triad is a set of three common findings in cholangitis: abdominal pain, jaundice, and fever. Reynolds' pentad includes the findings of Charcot's triad with the presence of septic shock and mental confusion. This combination of symptoms indicates worsening of the condition.