**Core Concept**
Ringer lactate solution is a type of isotonic crystalloid fluid used for fluid resuscitation and maintenance, containing sodium chloride, sodium lactate, potassium chloride, and calcium chloride. It is designed to mimic the electrolyte composition of human blood plasma and is commonly used in various clinical settings.

**Why the Correct Answer is Right**
Ringer lactate solution contains sodium chloride (NaCl), sodium lactate (C3H5NaO3), potassium chloride (KCl), and calcium chloride (CaCl2) as its primary components. The sodium lactate in Ringer lactate helps to buffer the solution and maintain a stable pH. The presence of calcium chloride is also crucial as it helps to stabilize cell membranes and maintain normal calcium levels in the body. The solution's electrolyte composition is essential for maintaining proper fluid balance and electrolyte homeostasis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Ringer lactate contains sodium chloride, not sodium gluconate.
**Option B:** This option is incorrect because Ringer lactate contains sodium lactate, not sodium acetate.
**Option C:** This option is incorrect because Ringer lactate contains calcium chloride, not calcium gluconate.

**Clinical Pearl / High-Yield Fact**
It is essential to note that Ringer lactate is not suitable for patients with severe metabolic acidosis, as the sodium lactate can worsen the condition. In such cases, other crystalloid fluids like normal saline or Hartmann's solution may be preferred.

**Correct Answer: C. Calcium gluconate.**