With Regard to a Landlord's Duty to Repair the Tenant's

With regard to a landlord's duty to repair the tenant's residence:

A) the landlord, under the traditional common law, had no duty to repair any living areas even if they were totally destroyed, but the tenant still had to pay rent for the term of the lease.
B) the landlord must, by law in most states today, provide an apartment that is fit for residential use.
C) the landlord may, under provisions negotiated in the lease, greatly limit the duty of repair he may owe to the tenant under law as long as these limitations do not violate public policy and are not unconscionable.
D) all of the above.