Final answer:
Elisabeth Kübler-Ross created the five stages of grief outlined in her 1969 book On Death and Dying. Her work in thanatology significantly contributed to the understanding of the emotional processes experienced by dying individuals.
Step-by-step explanation:
The psychologist who created the theory on the stages of death and dying is Elisabeth Kübler-Ross. She observed people who were in the process of dying and found that there were common threads in their experiences. Kübler-Ross outlined these observations in her 1969 book titled On Death and Dying, where she introduced the five stages of grief: denial, anger, bargaining, depression, and acceptance. Her work provided groundbreaking insights into the emotional journey of terminal patients and opened doors for further study in thanatology, the systematic study of death and dying. The five stages of grief can manifest in any order, and not all individuals may experience each stage. Moreover, a patient's response to their impending death, if deeply entrenched in denial, may prolong their stay in that phase, inhibiting their progress toward acceptance.