Answer: Option d
The y-intercept is 40. This is the cost of registration.
Explanation:
Note that in this problem we have 2 variables:
x: number of months
y: average community pool membership cost
The linear equation that models the equation is:

Note that the equation is increasing, that is, as x increases, the variable y increases as well.
To find the interception of the line with the axis and we must do x = 0


This means that the minimum value that the variable y can take is

In other words
represents the minimum cost, that is, the registration cost.
The answer is the option d.