Sandy is considering moving from her apartment into a small house with a fenced yard. The apartment is noisy, and she has difficulty studying. In addition, the fenced yard would be great for her dog. The distance from school is much the same from the house and from the apartment. The apartment costs $750 per month, and she has two months remaining on her lease. The lease cannot be broken, so Sandy must pay the last two months of rent whether she lives there or not. The rent for the house is $450 per month, plus utilities, which should average $100 per month. The apartment is furnished; the house is not. If Sandy moves into the house, she will need to buy a bed, dresser, desk, and chair immediately. She thinks that she can pick up some used furniture for a good price.

Which of the following costs is irrelevant to Sandy’s decision to stay in the apartment or move to the house?
  a.  House rent of $450 per month
  b.  Utilities for the house of $100 per month
  c.  The noise in the apartment house
  d.  The cost of the used furniture
  e.  The last two months of rent in the apartment