This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Concept of Health & Disease, Subject name: Social & Preventive Medicine
Disease which shows cyclical trend:- 
Select and explain. 
A. Malaria, B. Diarrhea, C. Measles, D. Tuberculosis
C: Measles
Answer: C: Measles 
Explanation: Time Distribution of Disease: - Periodic fluctuations: 1. Cyclical Trend - Fluctuations in every few years Ex - Measles, Rubella, Influenza Measles every 2-3 years Rubella every 5-8 years Influenza show maximum cyclical trends d/t antigenic shift/drift 2. Seasonal Trend - Disease that increases every paicular season Ex - Malaria/Dengue in Rainy Season, I in winter Season 3. Epidemic Trend - Sho term fluctuations Ex-Food poisoning, Bhopal Gas tragedy 4. Secular Trend - Long term fluctuations Ex - Non-communicable disease ( CHD, HTN etc)