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
In WHO classification of periradicular diseases code no. KO4.4 represents 
Select and explain. 
A. Acute apical periodontitis, B. Chronic apical periodontitis, C. Periapical abscess, D. Radicular cyst
A: Acute apical periodontitis
Answer: A: Acute apical periodontitis 
Explanation: WHO classification of periradicular diseases

KO4.4….acute apical periodontitis
KO4.5…chronic apical periodontitis
KO4.6…periapical abscess with sinus
KO4.7…periapical abscess without sinus
KO4.8….radicular cyst