A man coming from mountain whose wife died 6 months prior says that his wife appeared to him and asked him to join her. The diagnosis is :a) Normal griefb) Grief psychosisc) Bereavement reactiond) Supernatural phenomenon
The information in this question :

Death of wife.
Seeing the deceased (wife).
Hearing the voice of deceased.
Symptoms for 6 months.

These are typical symptoms of normal grief (bereavement reaction). Symptoms of grief may last 6 months - 12 months (According to Niraj Ahuja, if symptoms persist for more than 6 months, then it is referred to as morbid grief. But all other standard text books mention that normal grief can last up to 1 year).

"A normal grief reaction lasts up to 12 months (mean 6 months)".

— Oxford

"The normal grief reaction may last upto one year but can vary within different cultures. The average duration is probably 6 months".

— Essentials of clinical psychiatry

"The normal grief reaction can last for 6-12 months".

—BK Puri
Note - Other guides have given option 'b' i.e. grief psychosis as the answer by saying that patient has features of psychosis (auditory hallucination). But they are wrong because seeing the deceased or hearing the voice of deceased may be a feature of normal grief.
These are not psychotic features :

"Seeing or hearing the voice of deceased may occur during normal grief".

—Oxford

"Seeing or hearing the voice of deceased may be a symptom of normal grief".

— Essentials of clinical psychiatry

"The patient may hear the voice of deceased or even may see the decreased".

—LT
Further the term grief psychosis has not been mentioned in any standard text book of psychiatry.
a
bc
ad
ac