Task: Question Answering
Input (English): Question: The stimulation of the carotid bodies: 
 Options:  <1> Decreases the pH of arterial blood. <2> PCO2 decreases in arterial blood. <3> Increases the arterial concentration of bicarbonate. <4> Increases the urinary excretion of sodium. <5> Lowers blood pressure
Output (English): 2