This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Wounds, Tissue Repair & Scars, Subject name: Surgery
A 36-year-old diabetic woman develops metabolic changes following salpingo-oophorectomy. Serum osmolality of the blood can be calculated from serum values of which of the following? 
Select and explain. 
A. Sodium, potassium, chloride, and bicarbonate, B. Sodium, potassium, urea, and hemoglobin, C. Sodium, potassium, glucose, and urea, D. Sodium, albumin, urea, and glucose
C: Sodium, potassium, glucose, and urea
Answer: C: Sodium, potassium, glucose, and urea 
Explanation: Serum osmolality is calculated from serum values of sodium, potassium, glucose, and BUN by using the formula 2(Na+K)+BUN/2.8+glucose/18.