Read the following statements. Identify which of them are true and which of them are false and select the correct option.
I. Ascaris, commonly known as pinworm, is responsible for causing ascariasis.
II. The acid present in the stomach acts as a physiological barrier and prevents microbial growth.
III. The pathogen responsible for causing elephantiasis is a fungus belonging to genus Microsporum.
IV Infection diseases like tetanus and pneumonia have been largely controller using vaccines.

Options

A. A - True, B - False , C - True , D - False
B. A -False , B - True, C - False , D - True
C. A -False , B - True, C - True , D - False
D. A -False , B - False, C - True , D - True

Answer

To determine the truthfulness of the given statements, let's analyze each one step by step:

### Step 1: Analyze Statement I
**Statement I:** Ascaris, commonly known as pinworm, is responsible for causing ascariasis.

- **Analysis:** Ascaris is actually known as the common roundworm, not pinworm. The pinworm is scientifically known as Enterobius vermicularis, which causes enterobiasis, not ascariasis. Therefore, this statement is **False**.

### Step 2: Analyze Statement II
**Statement II:** The acid present in the stomach acts as a physiological barrier and prevents microbial growth.

- **Analysis:** The stomach contains hydrochloric acid (HCl), which creates an acidic environment. This low pH effectively inhibits the growth of many microbes, acting as a barrier against pathogens. Therefore, this statement is **True**.

### Step 3: Analyze Statement III
**Statement III:** The pathogen responsible for causing elephantiasis is a fungus belonging to genus Microsporum.

- **Analysis:** Elephantiasis is caused by filarial worms, specifically Wuchereria bancrofti, and not by a fungus. The genus Microsporum is associated with fungal infections like ringworm. Therefore, this statement is **False**.

### Step 4: Analyze Statement IV
**Statement IV:** Infectious diseases like tetanus and pneumonia have been largely controlled using vaccines.

- **Analysis:** Vaccines are indeed available for both tetanus and certain types of pneumonia (such as those caused by Streptococcus pneumoniae). Vaccination has significantly reduced the incidence of these diseases. Therefore, this statement is **True**.

### Summary of Statements:
- **Statement I:** False
- **Statement II:** True
- **Statement III:** False
- **Statement IV:** True

### Final Conclusion:
The true statements are II and IV, while I and III are false. Therefore, the correct option based on the analysis is that statements II and IV are true.

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