This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
For FITTER the shortest needle length in Pens should be....... mm? 
Select and explain. 
A. 4, B. 5, C. 6, D. 8
A: 4
Answer: A: 4 
Explanation: Ans. A. 4FITTER a congress which made new guidelines to help people on injections & pumps in Diabetes. We should use the shortest needle size (4mm for pens & 6mm for syringes].