What approximate percent of all bacteria are harmless and can even be beneficial to humans?

• A. Less than 10%
• B. Around 25%
• C. About 50%
• D. Over 90%

Answer: (D)

Verified step by step guidance

1. Understand the context: Bacteria are a diverse group of microorganisms, and their relationship with humans can be harmful, neutral, or beneficial.
2. Recall that the human body hosts a vast number of bacteria, many of which play essential roles in processes like digestion, immune system function, and protection against harmful microbes.
3. Recognize that scientific studies estimate that the majority of bacteria are not harmful to humans; in fact, many are beneficial or harmless.
4. Based on microbiological research, the approximate percentage of bacteria that are harmless or beneficial to humans is over 90%.
5. Therefore, when choosing from the given options, the correct answer reflects that more than 90% of bacteria fall into the harmless or beneficial category.