What is the smallest subset 365 can fit into?

The set of the number of days that a year can have.

Step-by-step explanation:

It is possible to have many examples that satisfy this description, but an example is:

- The set of the number of days that a year can have.

Let A be the set of the number of days that a year can have, the subsets are 365, and 366 (Leap Year)

So, A = {365, 366}.