Answer:
b. Both incremental and iterative development.
Step-by-step explanation:
Agile software development is based on both incremental and iterative development. It is an iterative method to software delivery in which at the start of a project, software are built incrementally rather than completing and delivering them at once as they near completion.
Incremental development means that various components of the system are developed at different rates and are joined together upon confirmation of completion, while Iterative development means that the team intends to check again components that makes the system with a view to revising and improving on them for optimal performance.
Agile as an approach to software development lay emphasis on incremental delivery(developing system parts at different time), team work, continuous planning and learning, hence encourages rapid and flexible response to change.