According to SAFe, a Feature should be sized to fit into what duration?

In SAFe, a Feature is a unit of work that delivers business value and fulfills a stakeholder need. A key characteristic of a Feature is its size. To ensure a continuous flow of value and enable effective planning and execution for an Agile Release Train (ART), Features are defined and sized to be completed within a single Program Increment (PI). If a business need is too large to fit into one PI, it is typically defined as an Epic and broken down into smaller Features.

A. One month is not a standard SAFe timebox for sizing Features; it is shorter than a typical PI.
B. One year is far too long for a Feature; work of this magnitude would be classified as a Portfolio Epic.
C. One Iteration is the timebox for a Story, which is a smaller component of a Feature.

1. Scaled Agile, Inc. (2023). Feature. Scaled Agile Framework. Retrieved from https://www.scaledagileframework.com/features-and-capabilities/. (See the introductory paragraph, which states, "Features are sized to fit in a Program Increment (PI).").