**Core Concept**
Bacterial vaginosis (BV) is a type of vaginal infection caused by an imbalance of the normal vaginal microbiota, characterized by an overgrowth of anaerobic bacteria such as Gardnerella vaginalis. This condition is distinct from a yeast infection and is often associated with an increase in pH levels in the vagina.

**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of bacterial vaginosis. BV is caused by an overgrowth of anaerobic bacteria, such as Gardnerella vaginalis, which thrive in environments with low oxygen levels. This leads to an imbalance of the normal vaginal microbiota, resulting in the characteristic symptoms of BV, including a foul odor and discharge. The increased pH levels in the vagina are a result of the anaerobic fermentation of glycogen by the bacteria.

**Why Each Wrong Option is Incorrect**
**Option A:** BV is not typically caused by a single pathogen, but rather by an imbalance of the normal vaginal microbiota. While Gardnerella vaginalis is often associated with BV, it is not the sole cause of the condition.
**Option B:** BV is not typically associated with an increase in white blood cells, but rather with a decrease in lactobacilli and an increase in anaerobic bacteria. The presence of white blood cells is more characteristic of a yeast infection or other type of vaginal infection.
**Option C:** BV is not typically treated with a single dose of antibiotic, but rather with a course of antibiotics that target the anaerobic bacteria. The treatment of BV often involves a combination of metronidazole and/or clindamycin.

**Clinical Pearl / High-Yield Fact**
A key feature of bacterial vaginosis is the presence of a "fishy" odor, which is often described as being similar to the smell of rotten fish. This is due to the release of amines by the anaerobic bacteria, which are responsible for the characteristic odor of BV.

**Correct Answer:** C