What Must a Possessor of Property Do in Order to Exercise

What must a possessor of property do in order to exercise reasonable care for the safety of his invitees?

A) He must take appropriate steps to protect them against only the dangers he is aware of on his premises.
B) He must take appropriate steps to protect them against dangerous on-premises conditions that he is aware of,or reasonably should discover,whether or not the invitee is likely to discover them on her own.
C) He must take appropriate steps to protect them against dangerous on-premises conditions that he is aware of,or reasonably should discover,and that the invitee is unlikely to discover.
D) He must take appropriate steps to protect them against only the abnormally dangerous on-premises conditions that he is aware of,and that the invitee is unlikely to discover.