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: Social & Preventive Medicine
Cluster testing is useful in detecting cases of 
Select and explain. 
A. Measles, B. Unimmunized children, C. Sexually transmitted infections, D. Completely immunized children in the age group 12-23 months
C: Sexually transmitted infections
Answer: C: Sexually transmitted infections 
Explanation: None