Final answer:
The true statement is that acquiring a cold for the second time in the same season is likely due to a different strain of the cold virus, as a secondary immune response to the same pathogen would typically be faster and stronger due to memory B cells. The correct option s A .
Step-by-step explanation:
The correct statement among the provided options is: d. If a patient acquires a cold for the second time in the same season, it is likely due to a different strain of the cold virus.
When considering the behavior of the immune system and its responses to pathogens, we know that a secondary immune response is much quicker and more robust than the primary immune response.
This rapid response is due to the actions of memory B cells that were created during the initial encounter with the antigen. These memory B cells facilitate a faster and stronger antibody production upon re-exposure to the same antigen.
Specifically, the secondary immune response overwhelms the pathogens quickly, often without causing symptoms, due to a higher amount of antibody production and no time delay in response.
Since the common cold can be caused by various strains of viruses, acquiring a cold a second time is likely a result of infection by a different strain, against which the body has not yet developed specific immunological memory. The correct option s A .