Final answer:
The correct answer is (b) Endemic. An endemic disease is one that is constantly present, usually at a low incidence, in a population, such as the common cold.
Step-by-step explanation:
An endemic disease is a disease that is constantly present, typically at a low incidence, within a population. Diseases such as the common cold are examples of endemic diseases because they are regularly found among people within a particular geographic area. Unlike epidemic diseases, which occur in an unusually high number of individuals in a population at the same time, or pandemic diseases that spread across large regions or worldwide, endemic diseases maintain a relatively steady presence without large-scale outbreaks.Therefore, the answer to the student's question is: An endemic disease is constantly present in a population; the common cold is an example. The correct option is (b) Endemic.