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
Ideal chin throat angle is: 
Select and explain. 
A. 120o, B. 70o, C. 130o, D. 90o
D: 90o
Answer: D: 90o 
Explanation: Neck–chin–angle
Cervicomental angle should be approximately 90 degrees. The angle is more obtuse in females as compared to males. The soft tissues sag in older individuals and contributes to less than ideal submental form.
Lip–chin–throat angle
The angle between the lower lip and deepest point along the neck chin contour should be approximately 90 degrees.
An obtuse angle is unaesthetic and more so as the angle increases. This often reflects:

Chin deficiency
Retropositioned mandible
Lower lip procumbency
Excessive submental fat
Low hyoid bone position