Which of the following statements is incorrect ?

Options

A. Aspirin is both analgesic and antipyretic .
B. Ampicillin is a natural antibiotic .
C. Salvarsan is toxix to human beings .
D. Some disinfectants are used as antiseptics in lower concentrations.

Explanation

To determine which statement is incorrect among the given options, let's analyze each statement one by one.

**Step 1: Analyze the first statement.**
- The first statement claims that "aspirin is both analgesic and antipyretic."
- Aspirin is known for its properties to relieve pain (analgesic) and to reduce fever (antipyretic).
- Therefore, this statement is **correct**.

**Step 2: Analyze the second statement.**
- The second statement claims that "ampicillin is a natural antibiotic."
- Ampicillin is actually a semi-synthetic derivative of penicillin, which means it is not a natural antibiotic but rather modified in a laboratory setting.
- Therefore, this statement is **incorrect**.

**Step 3: Analyze the third statement.**
- The third statement claims that "Selversun is toxic to human beings."
- Selversun (also known as silver sulfadiazine) can indeed be toxic and is used with caution.
- Therefore, this statement is **correct**.

**Step 4: Analyze the fourth statement.**
- The fourth statement claims that "some disinfectants are used as antiseptics in lower concentrations."
- This is true as certain disinfectants can be effective as antiseptics when diluted to lower concentrations.
- Therefore, this statement is **correct**.

**Conclusion:**
After analyzing all the statements, we find that the only incorrect statement is the second one, which claims that "ampicillin is a natural antibiotic."

**Final Answer:**
The incorrect statement is: "Ampicillin is a natural antibiotic."

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