In the following question, out of the four alternatives, select the alternative which is the best substitute for the given words/sentence.
Place or insert between one thing and another

* Interpose: Means to place or insert between one thing and another.
Oust: Drive out or expel someone from a position or place.

Efface: Erase a mark from a surface.

Purge: Rid someone or something of an unwanted quality, condition, or feeling.