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
Generation time in epidemiology is defined as ? 
Select and explain. 
A. The interval between marriage and the bih of first child, B. The interval of time between the receipt of infection by host and maximal infectivity of the host, C. The interval of time between primary case and secondary cases, D. Interval of time between invasion by infectious agent and appearance of first sign or symptom of the disease in question
B: The interval of time between the receipt of infection by host and maximal infectivity of the host
Answer: B: The interval of time between the receipt of infection by host and maximal infectivity of the host 
Explanation: Ans. is 'b' i.e., Interval of time between receipt of infection by the host and maximal infectivity of the host