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
Abnormal muscle activity results in 
Select and explain. 
A. Bruxism, B. nail biting, C. Tongue thrusting, D. thumb sucking
C: Tongue thrusting
Answer: C: Tongue thrusting 
Explanation: None