Which of the following best describes the action of germicidal chemicals?

• A. They only inhibit the growth of microorganisms without killing them.
• B. They sterilize by removing all organic material from surfaces.
• C. They are effective only against viruses, not bacteria or fungi.
• D. They kill or inactivate microorganisms on surfaces.

Answer: (D)

Verified step by step guidance

1. Understand the term 'germicidal chemicals': these are agents designed to kill or inactivate microorganisms such as bacteria, viruses, and fungi on surfaces.
2. Differentiate between terms: 'inhibit growth' refers to bacteriostatic or fungistatic actions, which do not kill but prevent multiplication, whereas 'germicidal' implies killing or inactivation.
3. Recognize that sterilization involves complete removal or destruction of all forms of microbial life, often requiring physical methods or specific chemical sterilants, not just germicidal chemicals.
4. Note that germicidal chemicals are generally broad-spectrum and effective against a variety of microorganisms, including bacteria, viruses, and fungi, not limited to one group.
5. Conclude that the best description of germicidal chemicals is that they kill or inactivate microorganisms on surfaces, which aligns with their intended use in disinfection.