Option 1: Frugal -> economical and thrifty in spending; careful with money.
Option 2: Lavish -> spending or giving generously and extravagantly; similar to prodigal, not opposite.
Option 3: Hardship -> severe suffering or difficulty; unrelated to spending habits.
Option 4: Persistent -> continuing firmly or stubbornly; no connection to the meaning of prodigal.
Hence, Option 1: Frugal -> "Prodigal" means wastefully extravagant or spending recklessly, while "frugal" means being economical and careful with resources, making them perfect antonyms -> correct