Final answer:
Option (c), The process by which viral parts come together inside a host cell to form new virions is known as assembly. This phase is crucial in the virus replication cycle, leading to the creation and release of new infectious particles.
Step-by-step explanation:
The various viral "parts" coming together to produce virions is described as assembly. This assembly phase is a critical part of the virus replication cycle, which includes attachment, penetration, uncoating, replication, assembly, and release. During the assembly phase, newly made viral proteins and genetic material come together within the host cell to form new virions.
These virions eventually leave the cell, often by a process called budding, which allows them to infect other cells while sometimes leaving the host cell intact but damaged. The envelope of the virus is derived from the host's membrane structures, and glycoproteins often help the virus latch onto a new host cell for subsequent infection cycles.