A 28-year-old lady has put on weight (10 kg over a period of 3 years) and has oligomenorrhoea followed by amenorrhea for 8 months. The blood pressure is 160/100 mm of Hg. Which of the following is the most appropriate investigation?
A
Serum electrolytes
B
Plasma cortisol
C
Plasma testosterone and ultrasound evaluation of pelvis