Question

what part of a virus determines which host the virus infects? plasma membrane nucleic acids surface proteins receptor molecules

Explanation:

Viruses use surface proteins to recognize and bind to specific receptors on host cells. This interaction is highly specific and determines which host (and often which type of cell within the host) the virus can infect. For example, the spike proteins on the surface of the SARS - CoV - 2 virus bind to ACE2 receptors on human cells. The plasma membrane is a feature of cells (not viruses, as viruses lack a true plasma membrane). Nucleic acids (DNA or RNA) carry the genetic information of the virus but do not directly determine host specificity. Receptor molecules are on the host cell, not the virus.

Answer:

C. surface proteins