What is the best definition of an allusion? (Select ALL That Apply)

Allusion is a figure of speech, in which an object or circumstance from unrelated context is referred to covertly or indirectly. It is left to the audience to make the direct connection. Where the connection is directly and explicitly stated by the author, it is instead usually termed a reference.

Explanation:

Basically its a reference to a known topic

an expression designed to call something to mind without mentioning it explicitly; an indirect or passing reference.