Pathogenic bacteria are responsible for all of the following except:

• A. causing infectious diseases in humans
• B. foodborne illnesses
• C. decomposition of organic matter in soil
• D. production of toxins

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the role of pathogenic bacteria. Pathogenic bacteria are microorganisms that cause diseases in their hosts, including humans, animals, and plants.
2. Step 2: Review the options given: causing infectious diseases in humans, foodborne illnesses, decomposition of organic matter in soil, and production of toxins.
3. Step 3: Recognize that pathogenic bacteria are directly involved in causing infectious diseases and foodborne illnesses, as well as producing toxins that contribute to disease symptoms.
4. Step 4: Identify that decomposition of organic matter in soil is primarily carried out by saprophytic bacteria, which are non-pathogenic and help recycle nutrients in the environment.
5. Step 5: Conclude that the exception is 'decomposition of organic matter in soil' because this process is not a function of pathogenic bacteria but of saprophytic bacteria.