**Core Concept**
Hyperchloremic metabolic acidosis occurs when there is an excessive loss of bicarbonate or an excessive gain of chloride ions, leading to a decrease in blood pH and an increase in chloride levels. This condition often results from the administration of chloride-rich fluids, such as normal saline, in patients with underlying conditions like diarrhea or kidney disease.

**Why the Correct Answer is Right**
The administration of normal saline, which is a chloride-rich fluid, can lead to hyperchloremic metabolic acidosis. This is because the chloride ions in normal saline can accumulate in the body and displace bicarbonate ions, leading to a decrease in blood pH. The kidneys attempt to compensate by increasing the excretion of hydrogen ions, but if the chloride load is excessive, it can overwhelm the kidneys' ability to compensate, resulting in hyperchloremic metabolic acidosis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a condition that leads to hyperchloremic metabolic acidosis. While it may be a cause of metabolic acidosis, it is not the most specific answer choice.
**Option B:** This option is incorrect because it refers to diabetic ketoacidosis, which is a cause of metabolic acidosis, but it is not typically associated with hyperchloremic metabolic acidosis. Diabetic ketoacidosis is often associated with a non-anion gap metabolic acidosis.

**Clinical Pearl / High-Yield Fact**
It is essential to remember that the administration of chloride-rich fluids, such as normal saline, can lead to hyperchloremic metabolic acidosis in patients with underlying conditions like kidney disease or diarrhea. This is a common pitfall in medical practice, and careful attention to fluid management is crucial to prevent this complication.

**Correct Answer: C. Normal saline.**