Correct Answer: B

Rationale: The correct answer is B: Prothrombin time (PT)/INR. Warfarin affects the clotting ability of the blood by inhibiting vitamin K-dependent clotting factors. Monitoring the prothrombin time (PT) and international normalized ratio (INR) is crucial to assess the effectiveness and safety of warfarin therapy. These tests help determine if the patient is within the desired anticoagulation range to prevent either clotting issues or excessive bleeding.

Correct Answer: A

Rationale: The correct teaching point for a patient prescribed methotrexate is to take folic acid supplements as prescribed. Methotrexate can lead to a folate deficiency, which is why supplementing with folic acid is essential to reduce the risk of side effects such as mouth sores, nausea, and liver problems.

Correct Answer: B

Rationale: The correct answer is B: Weight gain. Olanzapine, an atypical antipsychotic, is known to cause significant weight gain and metabolic syndrome. It is crucial for healthcare providers to closely monitor patients for these side effects to prevent complications and provide appropriate interventions.

Correct Answer: D

Rationale: Cracks at the corners of the mouth, known as angular cheilitis, can be a sign of vitamin B deficiency, specifically B2 (riboflavin) or B3 (niacin). The nurse should ensure that the client receives adequate B vitamins through foods rich in these nutrients or supplements to address the deficiency, which can help improve the condition of the client's mouth.

Correct Answer: C

Rationale: The client's statement that they should take ranitidine with meals indicates a need for further teaching. Ranitidine is typically taken at bedtime or before meals to be most effective in reducing stomach acid. Taking it with meals may not provide the optimal therapeutic effect.