Final answer:
d) has a psychological disorder.
Sebastian is experiencing severe symptoms that interfere with his daily life, such as deep sadness, inability to work or attend school, and feelings of hopelessness, which suggest he has a significant psychological disorder, likely major depression.
Step-by-step explanation:
Based on the symptoms described, Sebastian most likely has a psychological disorder. Depression is a serious health condition which can manifest in both emotional and physical symptoms. The situation mentioned describes Sebastian experiencing a deep sadness, an inability to carry out daily functions such as going to work or attending school, and questioning the meaning of life. This collection of symptoms indicates that his condition is beyond normal life challenges and significantly impacts his daily functioning.
Depression symptoms can include feelings of hopelessness, sleep and eating issues, withdrawal from social activities, and a persistent sense of worthlessness or guilt. When these symptoms are severe enough to cause distress and interfere with a person's ability to function, as in Sebastian's case, they suggest a psychological disorder, likely a major depressive episode, that requires professional attention.