The first antibiotic was discovered accidently by __A___ while working on __B__ .

Options

A. A-Waksman , B-Streptococcus
B. A-Fleming, B-Penicillium notatum
C. A-Waksman, B-Bacillus brevis
D. A-Fleming, B-Staphylococci

Answer

**Step-by-Step Solution:**

1. **Identify the Scientist**: The first antibiotic was discovered accidentally by Alexander Fleming. He is a well-known bacteriologist who made significant contributions to the field of microbiology.

2. **Identify the Microbe**: While working on Staphylococcus bacteria, Fleming made his discovery. Staphylococcus is a genus of bacteria that can cause various infections in humans.

3. **Accidental Discovery**: Fleming observed that a mold was growing in one of his culture plates, and around this mold, the Staphylococcus bacteria could not grow. This observation led him to investigate further.

4. **Identify the Mold**: The mold that Fleming observed was identified as Penicillium notatum. This mold produced a substance that inhibited the growth of Staphylococcus bacteria.

5. **Naming the Antibiotic**: The substance produced by Penicillium notatum was named penicillin, which became the first widely used antibiotic.

6. **Conclusion**: Therefore, the answer to the question is:
- A: Alexander Fleming
- B: Staphylococcus

**Final Answer**: The first antibiotic was discovered accidentally by **A: Alexander Fleming** while working on **B: Staphylococcus**.

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