This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Epidemiology, Subject name: Social & Preventive Medicine
All of the following are true about the Herd immunity for infectious disease except 
Select and explain. 
A. It refers to group protection beyond what is afforded by the protection of immunized individuals, B. It is likely to be more for infections that do not have a sub clinical phase, C. It is affected by the presence and distribution of alternative animal hosts, D. In the case of tetanus it does not protect the individual
B: It is likely to be more for infections that do not have a sub clinical phase
Answer: B: It is likely to be more for infections that do not have a sub clinical phase 
Explanation: The herd structure not only involves host population belonging to the herd species but also the presence and distribution of alternative animal hosts and possible insect vectors as well as those environmental and social factors that or or inhibit the spread of infection from host to host Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 110