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: Dental
Customized material as cold pulp testing agent available as deodorant like cane is: 
Select and explain. 
A. Dry ice., B. Green endo ice., C. Ethylchloride., D. All of the above.
B: Green endo ice.
Answer: B: Green endo ice. 
Explanation: None