Section 27 of the Sale of Goods Act, 1930 deals with the rules for transfer of property (title) in goods from seller to buyer. It specifies when ownership passes depending on the nature of goods - specific goods are transferred when the contract is made, unascertained goods when they are ascertained, and future goods when they are in a deliverable state. The other options - authority, interest, and risk - are related concepts but Section 27 specifically addresses transfer of title/property.