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
True for effect of smoking on prognosis of periodontal diseases following scaling and prophylaxis is 
Select and explain. 
A. Increase in clinical attachments, B. Increase in width of attached gingiva, C. Reduction in negative influence of smoking due to increased level of plaque control, D. Increase in neutrophilic response
C: Reduction in negative influence of smoking due to increased level of plaque control
Answer: C: Reduction in negative influence of smoking due to increased level of plaque control 
Explanation: None