Option 1 -> Thrifty means economical and careful with money, which is the same as frugal.
Option 2 -> Prodigal means wasteful and extravagant with money, the opposite of frugal.
Option 3 -> Extravagant means spending money excessively without restraint, an antonym of frugal.
Option 4 -> Affluent means wealthy or rich, which describes financial status rather than spending behavior.
Hence, Option 1: Thrifty -> Both frugal and thrifty describe someone who is careful, economical, and avoids unnecessary spending, making them perfect synonyms. -> correct