**Core Concept**
Human fibroblast cell lines are commonly used in virology for the cultivation and study of various viruses. This is because these cells provide a suitable environment for viral replication, allowing researchers to understand viral pathogenesis and develop effective treatments.

**Why the Correct Answer is Right**
Poliovirus, a member of the Picornaviridae family, requires a human cell line for replication. Human fibroblast cell lines, such as HeLa or MRC-5, provide the necessary cellular machinery and receptors for poliovirus to attach, enter, and replicate within the host cell. The Sabin vaccine, a live attenuated vaccine, was developed using a human fibroblast cell line, further highlighting the importance of these cells in poliovirus research.

**Why Each Wrong Option is Incorrect**
**Option A:** Adenovirus can be grown in a variety of cell lines, including human epithelial cells, but it is not specifically dependent on human fibroblasts for replication.
**Option C:** HIV requires a CD4+ T-cell line, such as MT-4 or CEM, for cultivation, not a human fibroblast cell line.
**Option D:** Measles virus can be grown in various cell lines, including Vero cells, but it is not specifically associated with human fibroblast cell lines.

**Clinical Pearl / High-Yield Fact**
When working with viruses, the choice of cell line is crucial for successful cultivation and replication. Human fibroblast cell lines are particularly useful for studying viruses that require human cells for replication, such as poliovirus.

**✓ Correct Answer: B. Poliovirus**