Final answer:
Primary prevention aims to prevent disease or illness before it starts, with 'b. Illness' being the correct answer. This is a fundamental aspect of public health, including vaccination, education, and hygiene practices.
Step-by-step explanation:
Primary prevention is the prevention of disease or illness before it happens. The answer to the fill-in-the-blank question is 'b. Illness'. Primary prevention strategies are crucial in the field of public health and include actions that aim to prevent the emergence and spread of diseases. Examples of primary prevention include vaccination, public health education, and maintaining proper hygiene such as washing hands regularly. The concept of prophylaxis underlines the methods of disease prevention and the importance of these strategies cannot be overstated, as they contribute to the overall health and wellbeing of individuals and communities.