What is Alternative Obligation?

Legal Definition
An obligation allowing the obligor to choose which of two things he will do, the performance of either of which will satisfy the instrument. Where the things which form the obj'ect of the contract are separated by a disjunctive, then the obligation is alternative. A promise to deliver a certain thing or to pay a specified sum of money, is an example of this kind of obligation. Civil Code La. art. 2066,
-- Black's Law Dictionary