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
'Squint' test is used as guide for selecting 
Select and explain. 
A. Shade of teeth, B. Shape of teeth, C. Length of teeth, D. None of the above
A: Shade of teeth
Answer: A: Shade of teeth 
Explanation: None