Final answer:
Elizabeth Kübler-Ross proposed five stages of grief as a response to difficult news or reality, such as a terminal illness. Denial, the first stage, acts as a defense mechanism to protect individuals from the unbearable truth.
Step-by-step explanation:
Elizabeth Kübler-Ross proposed five stages of grief: denial, anger, bargaining, depression, and acceptance. These stages describe the emotional reactions of individuals when facing difficult news or reality, such as a terminal illness. Denial is the first stage, where a person may not want to believe they are dying. This stage acts as a defense mechanism to protect them from the unbearable truth. The stages may occur in different orders, and some people may not experience all of them.