The correct answer and explanation is:

c. Denial

The nurse should identify that the client is experiencing the stage of denial in the grief process. Denial is a common psychological defense mechanism that individuals may exhibit when faced with a stressful or overwhelming situation, such as the prospect of open heart surgery. It involves a refusal to accept or acknowledge the reality of the situation. In this case, the client's statement of being confident to go home shortly after surgery demonstrates a denial of the potential challenges and recovery process associated with such a procedure.

Explanation for the other options:

A . Anger: Anger is a stage of grief characterized by feelings of resentment, frustration, and hostility. It is common for individuals to experience anger as part of the grief process, but the client's statement does not indicate anger.

B. Depression: Depression is another stage of grief marked by feelings of sadness, hopelessness, and loss. While it is normal for individuals to experience some level of anxiety or sadness before undergoing surgery, the client's statement does not specifically reflect depression.

d. Acceptance: Acceptance is the final stage of grief, where individuals come to terms with their situation and find a sense of peace or resolution. The client's statement indicates a lack of acceptance as they are denying the potential impact of the surgery and its recovery process.

b. A decreased level of consciousness and vomiting

Explanation:

When receiving report on four clients, the nurse should first collect data about the client who has a decreased level of consciousness and vomiting. This combination of symptoms suggests a potentially serious condition that requires immediate atention and assessment. It could indicate a neurological or gastrointestinal issue, and further evaluation is necessary to determine the underlying cause and provide appropriate interventions.

Explanation for the other options:

a. Cellulitis accompanied by a low-grade fever:

While cellulitis and a low-grade fever require atention, they are not as immediately critical as a decreased level of consciousness and vomiting. The nurse should prioritize assessing the client with altered consciousness and vomiting due to the potential for more urgent interventions.

c. A pain rating of 7 on a scale from 0 to 10 after receiving analgesia 30 min ago:

Although the client's pain rating of 7 indicates ongoing pain, it is not as immediately critical as a decreased level of consciousness and vomiting. The nurse should first address the client with altered consciousness to determine the cause and provide appropriate interventions before assessing and managing pain in other clients.

d. Type 2 diabetes mellitus and a blood glucose level of 160 mg/dL:

While elevated blood glucose levels in a client with type 2 diabetes require atention and management, they are not as immediately critical as a decreased level of consciousness and vomiting. The nurse should first assess the client with altered consciousness to identify the cause and provide prompt interventions.

In summary, when receiving report on four clients, the nurse should first collect data about the client who has a decreased level of consciousness and vomiting. These symptoms indicate a potentially serious condition requiring immediate assessment and intervention.