How many different classes of partners are required for a limited partnership to be legal?

For a limited partnership to be considered legal, it must consist of at least two different classes of partners: general partners and limited partners.

General partners are those who manage the business and are personally liable for the debts and obligations of the partnership. This means they take on full responsibility for any losses or legal issues that arise. In contrast, limited partners invest in the partnership but do not partake in its management and have their liability limited to the amount of their investment. This distinction is crucial because it provides an investment structure that allows individuals to contribute capital without the risk of losing more than they invested.

In summary, the requirement for having both general and limited partners is fundamental to forming a limited partnership, making the correct answer the necessity for two distinct classes of partners.