What must virus particles do in order to replicate?

To replicate, virus particles must infiltrate a host cell. Viruses are not living organisms and cannot reproduce or carry out metabolic processes on their own. They require the cellular machinery of a host organism to replicate their genetic material and produce new viral particles.

Once a virus successfully attaches to a specific host cell, it enters the cell and hijacks the host's biological processes to synthesize viral components. This process involves using the host's ribosomes, enzymes, and nucleic acids to create copies of its genome and to assemble new virus particles. After replication, the newly formed viruses are released from the host cell, often destroying it in the process, thus allowing the cycle of infection to continue.

The other choices do not accurately reflect the necessary conditions for viral replication, as viruses cannot reproduce independently, spread through air without contact, or attach to inorganic materials for replication purposes.