The fundamental modernization of ribbed groin vaults in Gothic cathedrals was to accommodate stained glass window. The ribbed groin vault is the connection of two or three barrel vaults yields a rib vault or ribbed vault when they are bordered with an armature of piped masonry often engraved in decorative patterns and associate groin vault is an older custom of vault structure.
I believe the answer to be C. checks and balances
Answer: Indentured servants
Economic factors , nationalist factors
