Which of the following is a common symptom of pesticide exposure?

Headaches are a common symptom of pesticide exposure due to the way many pesticides interact with the human nervous system and various biological processes. When individuals are exposed to pesticides, especially through inhalation or skin contact, they may experience a range of symptoms related to acute toxicity. Symptoms like headaches can occur as a result of the body's reaction to the chemicals as it tries to detoxify and eliminate them. This can lead to central nervous system disturbances, which manifest as headaches or migraines.

In contrast, increased strength and improved vision are not typically associated with pesticide exposure. Exposure generally leads to adverse health effects rather than any improvements in physical capabilities or sensory functions. Bacterial infections may occur in some contexts, but they are not direct symptoms of pesticide exposure; rather, such infections would arise from different mechanisms, such as compromised immune response due to toxicity or exposure to unsanitary conditions.