Final answer:
The relation between the months of the year and the number of days in each month is a function because every month is associated with a unique and singular number of days.
Step-by-step explanation:
The student's question examines whether a certain mapping between two sets constitutes a function. Specifically, it involves the months of the year as the first set and the possible number of days per month as the second set. In mathematics, a relation between two sets is a function if and only if each element of the first set (in this case, each month) is associated with exactly one element of the second set (a specific number of days). Given that each month maps to only one possible number of days (ignoring leap year variations), yes, the relation described is indeed a function. Each month of the year consistently corresponds to a single, unique count of days, whether that number is 28, 30, or 31 days.