Final answer:
The man with lung cancer is in the bargaining stage of grief, attempting to negotiate for a cure by quitting smoking. However, lung cancer is often incurable, especially when diagnosed late, and the leading cause is tobacco smoke exposure.
Step-by-step explanation:
The stage of grief a man with lung cancer is in when asking his doctor to confirm that quitting smoking will cure him can be identified as bargaining. According to the Kübler-Ross model, in the bargaining stage, an individual attempts to negotiate or make deals to postpone the inevitable, such as death from terminal illness. This stage is preceded by denial and anger and followed by depression and acceptance.
In the case of a terminal illness like lung cancer, which is often diagnosed late and is the most common cause of cancer-related death, most cases cannot be cured. This is especially true if the cancer has already spread beyond its original site, making it resistant to treatments like surgery, chemotherapy, and radiation therapy. Even with the cessation of smoking, the damage done by years of tobacco exposure, which is the leading cause of lung cancer, may not be reversible, and the associated risks of lung cancer remain significantly higher for smokers than non-smokers.