Choose the correct word which can substitute the given phrase from th…

The correct answer is Option (3) → Epitaph

An epitaph is a short piece of writing in memory of a dead person, cut on the tomb or gravestone. The word comes from the Greek epi (upon) + taphos (tomb), that is, words written "upon a tomb". The question asks for one word for an inscription on a tomb, which is an epitaph.
Example: The epitaph on his grave read, "He lived for others."

Why the Other Options are Incorrect?

Option 1: Espionage — Incorrect. Espionage is the practice of spying to obtain secret information, usually about a country or a company.
Example: The engineer was arrested on charges of espionage.

Option 2: Epilogue — Incorrect. An epilogue is a section at the end of a book or play that comments on what has happened; it is not written on a tomb. It comes from the Greek epi (in addition) + logos (speech), so the shared "epi-" does not make it a tomb word.
Example: The epilogue tells us what became of the characters ten years later.

Option 4: Elegy — Incorrect. An elegy is a sad poem written in memory of someone who has died; it mourns the dead person but is not an inscription on the tomb.
Example: Thomas Gray's "Elegy Written in a Country Churchyard" is a famous English poem.