Rachel is deciding whether to remain in the home she has lived in for the past ten years, which is located very near her work, or to move into a newer home that is located in the suburbs further from her job. The old house was purchased for $160,000 and has a market value of $220,000. The new home can be purchased for $285,000. Which of the following is not relevant to Rachel's decision?

a. Driving distance to work
b. Cost of the old house
c. Market value of the old house
d. Cost of the new house