Which type of vaccine uses specific parts of a virus or bacteria, such as proteins or sugars, to stimulate an immune response? 

Subunit, recombinant, or conjugate vaccines use specific parts of a virus or bacteria, such as proteins or sugars, to stimulate an immune response. These vaccines may use a small part of the microbe or a harmless piece of the microbe, which is enough to trigger an immune response without causing the disease. The immune system recognizes the specific part of the microbe as foreign and produces a response, including the production of antibodies, that will protect against future exposure to the actual pathogen. Examples of subunit, recombinant, or conjugate vaccines include HPV, Hepatitis B, Haemophilus influenzae type b (Hib), and Pneumococcal Vaccine.