Answer:
The correct answer is the last option, that is, multigene families are similar or identical genes, whose evolution took place by gene duplication.
Step-by-step explanation:
A member of a family of the associated proteins encrypted by an array of identical genes is known as a multigene family. It is considered that the origination of the multigene families has resulted due to the variation and duplication of a single ancestral gene.
The multigene families make the assembly of the proteins comparatively quickly, as it assists in the simultaneous transcription of various genes at distinct locations.