A tenant moved out of the dormitory at a state college and rented a one-bedroom apartment not far from campus. She signed a one-year lease and moved in on September 1, two weeks before classes began. Rent was specified in the lease to be $750 per month. When classes began, she started walking from her apartment building to the college, and quickly found that the walk, much of which was on a busy street with no sidewalks, was much more difficult than she had thought it would be. After a month, the tenant moved out when she found another apartment. She sent the landlord the keys, together with a note apologizing for the sudden departure. The landlord immediately cleaned up the apartment and placed an ad in the paper. Since school had already started, it was difficult to find someone to take the apartment, and when the landlord found someone, the rent had to be lowered to $620. Which of the following is the most accurate statement concerning the landlord's rights?

(A) The landlord was obligated to attempt to re-rent the property to help lower the tenant's damages, but will be able to recover his costs of the re-rental, any unpaid rent until he re-rented the apartment, and $130 per month for the balance of the lease.
(B) The landlord was not obligated to attempt to re-rent the property to help lower the tenant's damages, but since he did he will be able to recover the costs of re-rental, any unpaid rent until he re-rented the apartment, and $130 per month for the balance of the lease.
(C) The landlord was obligated to attempt to re-rent the property to help lower the tenant's damages, but will be unable to recover the costs of the re-rental since it was mandatory; however, he will be able to recover the difference in rent between what the tenant promised to pay and the amount secured on the re-rental.
(D) The landlord was not obligated to attempt to re-rent the property to help lower the tenant's damages, and under these facts the tenant is only liable for the unpaid rent up to the time the landlord retook the apartment, and is not liable for any unpaid rent up to the re-renting, nor for any deficiency in rent.