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: Microbiology
Tests of chicken pox-a) FAMAb) ELISAc) Widald) PCR 
Select and explain. 
A. abd, B. bcd, C. abc, D. ab
A: abd
Answer: A: abd 
Explanation: None