Final answer:
Individuals or firms with property ownership have comprehensive property rights, including entering into contracts and owning different kinds of properties. Property rights and contractual rights are foundational for business transactions and essential for economic growth.
Step-by-step explanation:
The entity that has most of the property rights of individuals, the ability to enter into contracts, and the authority to buy, sell, and own all kinds of properties are individuals or firms with property ownership. This possession includes both physical property and intangible assets like training and experience. Property rights are crucial as they allow for the highest and fullest use of one's property, including trade and sales, while contractual rights are based on these property rights, offering legal recourse in the event of noncompliance. These rights are vital for facilitating business transactions and contributing to economic growth by encouraging standard of living improvements through increased output and rising incomes.