The main reason why antibiotics could not always treat the bbacteria-mediated diseases is

Options

A. insensitivity of the individual following prolonged exposure to anitbiotics
B. inactivation of antibiotics by bacterial enzymes
C. decreases efficiency of immune system
D. the development of mutant bacterial strains resistant to antibiotics.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the main reason why antibiotics are not always effective in treating bacteria-mediated diseases.

2. **Identifying the Problem**: Antibiotics are designed to kill or inhibit the growth of bacteria. However, their effectiveness can be compromised.

3. **Overuse of Antibiotics**: One of the primary reasons antibiotics may fail is the overuse of these medications. When antibiotics are used excessively, bacteria can be exposed to them frequently.

4. **Development of Resistance**: With repeated exposure to antibiotics, some bacteria may undergo mutations. These mutations can lead to the development of bacterial strains that are resistant to the antibiotics.

5. **Mutant Strains**: The resistant strains, often referred to as mutant strains, have genetic changes that provide them with an advantage over non-mutant strains. This means they can survive and thrive even in the presence of antibiotics.

6. **Selective Advantage**: Unlike non-mutant strains, which are susceptible to antibiotics, mutant strains are selective and can withstand the effects of these drugs. This selective advantage allows them to proliferate.

7. **Conclusion**: Therefore, the main reason antibiotics cannot always treat bacteria-mediated diseases is the development of antibiotic-resistant mutant strains of bacteria.

**Final Answer**: The main reason why antibiotics could not always treat bacteria-mediated diseases is the development of antibiotic-resistant mutant strains.

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