Which of the following compounds are not used as disinfectants? A....

Antiseptics and disinfectants are also chemicals that either kill or prevent the growth of microorganisms. Antiseptics are applied to living tissues such as wounds, cuts, ulcers and diseased skin surfaces. Examples are furacine, soframicine, etc. Commonly used antiseptic, Dettol is a mixture of chloroxylenol and terpineol. Bithionol (the compound is also called bithional) is added to soaps to impart antiseptic properties. Protonsil is an antibiotic, whereas veronal is a tranquilizer which is used for the treatment of stress and mild or severe mental diseases.

So, Veronal and Prontosil are not used as disinfectant.