Chloroamphenicol is an `:`

Options

A. antifertility drug
B. antihistamines
C. antiseptic and disinfectant
D. antibiotic `-` broad spectrum

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to identify what type of substance chloramphenicol is. We have four options to consider: anti-fertility drug, antihistamines, antiseptic and disinfectant, and antibiotic broad spectrum.

2. **Analyzing the Options**:
- **Anti-fertility drug**: These are medications used to prevent pregnancy. Chloramphenicol does not fit this category.
- **Antihistamines**: These are drugs that counteract the effects of histamine in the body, often used for allergies. Chloramphenicol is not an antihistamine.
- **Antiseptic and disinfectant**: These are substances used to kill or inhibit the growth of microorganisms. While chloramphenicol has antibacterial properties, it is not primarily classified as an antiseptic or disinfectant.
- **Antibiotic broad spectrum**: This refers to antibiotics that are effective against a wide range of bacteria. Chloramphenicol is known for its broad-spectrum antibiotic properties.

3. **Conclusion**: After analyzing all the options, it is clear that chloramphenicol is best classified as an "antibiotic broad spectrum." Therefore, the correct answer is option D.

**Final Answer**: Chloramphenicol is an antibiotic broad spectrum.

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