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: Microbiology
Clinical features of H. influenzae is/are: 
Select and explain. 
A. Most frequently by biotype-I of type B strain, B. Occur in children (<2 years of age) due to absence of PRP antibodies, C. Most common complication of its meningitis – subdural effusion, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: None