This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'A 28-year-old lady has put on weight (10 kg over a period of 3 years) and has oLigomenorrhoea followed by amenorrhoea for 8 months. The blood pressure is 160/100 mm of Hg. Which of the following are the most appropriate investigations - \nSelect and explain. \nA. Serum electrolytes, B. Plasma cortisol, C. Plasma testosterone and ultrasound evaluation of pelvis, D. T3, T4 and TSH', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]