Which of the following can stimulate the vomiting center?

The vomiting center is primarily located in the medulla oblongata of the brain and is responsible for the coordination of vomiting. One of the main stimuli for this center is vestibular stimulation, which can occur due to movements that affect balance and equilibrium, such as those experienced during travel or in situations that provoke motion sickness. When the vestibular system detects these changes, it sends signals to the vomiting center, which may trigger the vomiting reflex as a protective mechanism to eliminate toxins or irritants from the gastrointestinal tract.

Increased appetite, increased blood pressure, and food intake typically do not have a direct stimulating effect on the vomiting center. Increased appetite might lead to more food intake and is generally associated with the normal urge to eat rather than a signal for vomiting. Increased blood pressure is not linked to vomiting but reflects physiological conditions that don't necessarily activate the vomiting reflex. Food intake is also not solely a stimulus for vomiting; rather, it's the resultant sensation of fullness or specific contents in the stomach that might provoke a reaction, rather than the act of eating itself. Thus, vestibular stimulation stands out as a clear factor in the activation of the vomiting center.