A large number of antibiotics have been isolated from

Options

A. Bacteria actinomycetes
B. Bacteria staphylococcus
C. Bacteria rhizobium
D. Acids

Answer

To solve the question "A large number of antibiotics have been isolated from," we can follow these steps:

### Step 1: Understand What Antibiotics Are
Antibiotics are substances that inhibit the growth of or kill microorganisms, particularly bacteria. They are commonly used to treat infections.

**Hint:** Remember that antibiotics are classified based on their spectrum of activity: broad spectrum and narrow spectrum.

### Step 2: Identify the Sources of Antibiotics
Antibiotics can be derived from various sources, including bacteria, fungi, and other microorganisms.

**Hint:** Focus on the common sources of antibiotics that are widely recognized in the field of microbiology.

### Step 3: Analyze the Given Options
The options provided are:
1. Bacteria, Actinomycetes
2. Bacteria, Staphylococcus
3. Bacteria, Rhizobium
4. Acids

Among these, Actinomycetes are a group of bacteria known for their ability to produce a large number of antibiotics.

**Hint:** Consider which of the options is specifically known for antibiotic production.

### Step 4: Recall Specific Examples
Actinomycetes, particularly the genus Streptomyces, are well-known for producing many antibiotics, such as streptomycin and tetracycline.

**Hint:** Think about the specific types of bacteria that are famous for antibiotic production.

### Step 5: Choose the Correct Answer
Based on the analysis, the correct answer is "Bacteria, Actinomycetes" as they are the primary source of a large number of antibiotics.

**Final Answer:** A large number of antibiotics have been isolated from **Bacteria, Actinomycetes**.

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