Concept:A trilogy is a set of three related literary or dramatic works, usually created by the same author.
Explanation:The word “trilogy” refers to three works that form a connected series.
These works are normally written or composed by the same author.
They may be three related plays, novels, or films, not necessarily one-act dramas or poems of equal length.
Thus, among the options, the most accurate definition is a sequence of three plays written by the same author.
Answer:C. sequence of three plays written by the same author.