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
All of the following statement about Kawasaki's disease are true except -a) It is the most common immune mediated vasculitis in childrenb) Coronary artery aneurysm is seen in 25% of patientsc) Intravenous immunoglobulin is indicated only in patients with coronary artery aneurysmd) Skin, mucus membranes and lymph nodes are involved 
Select and explain. 
A. a, B. ac, C. ad, D. b
B: ac
Answer: B: ac 
Explanation: None