The anion gap is determined from which of the following groups of electrolytes?
A) Sodium, chloride, potassium, and calcium
B) Sodium, chloride, potassium, and HCO₃⁻
C) TCO₂, chloride, potassium, and magnesium
D) Sodium, chloride, potassium, and phosphorus
Answer: Sodium, chloride, potassium, and HCO₃⁻