Final answer:
A symptom of bacterial vaginosis is a fishy odor, which is a hallmark characteristic of the condition. Other possible symptoms can include a grayish-white discharge and burning sensations, but a fishy odor is most common and distinct for this diagnosis. Therefore, the correct option is c.
Step-by-step explanation:
A common symptom of bacterial vaginosis is a fishy odor, which is often more noticeable after sexual intercourse. Other possible symptoms include a grayish-white vaginal discharge and a burning sensation during urination or irritation, but itching is less common. It's important to note that sometimes bacterial vaginosis can occur without any symptoms. If the condition is symptomatic, the fishy odor is a hallmark characteristic. Options like greenish-yellow discharge and painful urination are more often associated with other conditions such as sexually transmitted infections.