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: Biochemistry
Synthesis of an immunoglobulin in membrane bound of secretory form is determined by - 
Select and explain. 
A. One turn to two turn joining rule, B. Class switching, C. Differential RNA processing, D. Allelic exclusion
C: Differential RNA processing
Answer: C: Differential RNA processing 
Explanation: None