Formaldehyde, ethylbenzene, and hydrogen sulfide are classified as toxic chemicals that pose health risks. Proper handling and safety measures are essential when dealing with these substances. Therefore, the correct answer is A. toxic.
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Formaldehyde, ethylbenzene, and hydrogen sulfide are classified as toxic substances, posing various health risks. They are commonly used in industrial processes but require careful handling due to their dangerous effects. Ensuring safety when dealing with these chemicals is crucial. ;