To determine an expected value based on the line of best fit, I would need the specific data points or a graphical representation of the line itself. However, without that information, I cannot reliably choose a value from the options provided (a) 230, (b) 310, (c) 480, or (d) 540.
If you can describe the trend of the data or provide additional context, I would be glad to help you interpret it! Alternatively, if you have the equation of the line of best fit, I could also assist in calculating the expected value for June 2015.