Final answer:
hnRNA is involved in transcription, where it serves as the precursor to mRNA before being processed into its mature form that participates in protein synthesis.
Step-by-step explanation:
hnRNA (heterogeneous nuclear RNA) is primarily involved in the process known as transcription. During transcription, the genetic information within a DNA segment is used to produce an RNA strand. hnRNA is the precursor form of mRNA (messenger RNA), which is then processed through splicing, capping, and addition of a poly-A tail to become mature mRNA. Mature mRNA leaves the nucleus to guide protein synthesis in the cytoplasm during a process called translation. Therefore, hnRNA is not directly involved in translation, replication, or DNA repair.