Multigene families are Multigene families are groups of enhancers that control transcription. sets of genes that are coordinately controlled. usually clustered at the telomeres. equivalent to the operons of prokaryotes. identical or similar genes that have evolved by gene duplication.

The correct answer is the last option, that is, multigene families are similar or identical genes, whose evolution took place by gene duplication.

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.  

it takes hundreds of years to become stable.

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