**Core Concept**
The question is testing the knowledge of viruses that can be transmitted through blood transfusions. Transfusion-transmitted viruses are pathogens that can be spread through the transfusion of infected blood products, posing a significant risk to recipients. These viruses can be classified into several categories, including hepatitis viruses, retroviruses, and others.

**Why the Correct Answer is Right**
The correct answer includes a list of viruses that are known to be transmitted through blood transfusions. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are well-documented examples of transfusion-transmitted viruses. HBV can cause acute and chronic liver disease, while HCV can lead to chronic liver disease and liver cancer. Both viruses are primarily transmitted through parenteral routes, including blood transfusions. **Option A:** Hepatitis B virus (HBV) and **Option C:** Hepatitis C virus (HCV) are the correct answers.

**Why Each Wrong Option is Incorrect**
**Option B:** HIV is primarily transmitted through sexual contact, parenteral exposure (e.g., needle sharing), and from mother to child during pregnancy, childbirth, or breastfeeding. While HIV can be transmitted through blood transfusions, it is not the primary mode of transmission, and other options are more accurate in the context of transfusion-transmitted viruses.

**Clinical Pearl / High-Yield Fact**
It is essential to note that blood banks and transfusion services implement rigorous screening measures to detect and prevent the transmission of transfusion-transmitted viruses. These measures include serological testing, nucleic acid testing (NAT), and donor questionnaire and interview.

**Correct Answer:** **A. Hepatitis B virus (HBV)** **and C. Hepatitis C virus (HCV)**