Answer:
Option C,
prevent unwanted enhancer/promoter interactions
Explanation:
An insulator sequence consists of several binding sites in clusters that corresponds to specific DNA-binding proteins and leads to specific intra- and inter-chromosomal interactions. Insulators acts as a blocker or barrier in all the cases as its main role is to prevent unwanted interactions between enhancer or promoter.
These are class of DNA sequence elements that protect genes from taking inappropriate signals coming from surrounding environment thereby protecting gene expression from its surroundings.
Hence, option C is correct
