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
An investigator want to know the similarity of the mean peak flow of expiratory rates and non-smokers, light smokers, moderate smokers, & heavy smokers. Which is statistical test of significance: 
Select and explain. 
A. One way ANOVA, B. Two way ANOVA, C. Student-t test, D. Chi square test
A: One way ANOVA
Answer: A: One way ANOVA 
Explanation: None