The correct answer is A. A small dose of the weakened virus is given to the patient so that antibodies can form.
Explanation:
The purpose of a vaccine is to stimulate the immune system of individuals and allow this to create antibodies that can appropriately respond to the virus. This is achieved by creating or producing a weakened or modified version of the virus, then giving this virus to the patient in a low dose that does not make the patient sick but allows his body to produce specific antibodies that can recognize and attack the virus appropriately. In this way, if the patient is in contact with the regular version of the virus its body will generate an appropriate immune response and stop the virus from triggering infection or make the patient sick. In this context, the statement that best describes how a vaccine works is "A small dose of the weakened virus is given to the patient so that antibodies can form".-
