**Core Concept**
Live vaccines are made from weakened or attenuated forms of a virus or bacteria, which stimulate an immune response without causing the full-blown disease. They are used to prevent infections such as measles, mumps, and rubella.

**Why the Correct Answer is Right**
The correct answer is **inactivated vaccines**, which are made from killed or inactivated pathogens. These vaccines do not contain live organisms and cannot cause the disease they are intended to prevent. Examples of inactivated vaccines include the flu vaccine and the HPV vaccine. Inactivated vaccines work by stimulating the immune system to produce antibodies against the pathogen, without causing any harm.

**Why Each Wrong Option is Incorrect**
**Option A:** Live, attenuated vaccines, such as the MMR vaccine, are indeed live vaccines and are used to prevent infections.
**Option B:** Conjugate vaccines, such as the pneumococcal conjugate vaccine, are made by attaching a weakened form of a pathogen to a carrier protein, but they are not live vaccines.
**Option C:** Subunit vaccines, such as the Hepatitis B vaccine, are made from specific components of a pathogen, but they do not contain live organisms and can be considered inactivated vaccines.

**Clinical Pearl / High-Yield Fact**
Inactivated vaccines are often used in individuals with weakened immune systems, such as those with HIV/AIDS or undergoing chemotherapy, because they cannot cause the disease they are intended to prevent.

**Correct Answer:** B. Conjugate vaccines.