What drug enhances the output of respiratory tract fluid by reducing the adhesiveness and surface tension of the fluid which facilitates the removal of viscous mucus?

Choice A rationaleGuaifenesin is an expectorant that increases the output of respiratory tract fluid by reducing the adhesiveness and surface tension of the mucus, facilitating the removal of viscous mucus.Choice B rationaleDextromethorphan is a cough suppressant that works on the cough center in the brain to reduce the urge to cough. It does not enhance the output of respiratory tract fluid.Choice C rationaleAcetylcysteine is a mucolytic that breaks down the chemical structure of mucus molecules, making the mucus less viscous, but it does not enhance the output of respiratory tract fluid by reducing adhesiveness.Choice D rationaleFlunisolide is an inhaled corticosteroid used to reduce inflammation in the airways. It does not enhance the output of respiratory tract fluid.