I . William Harvey disappproved the 'good humour' hypothesis of health.
II. Health can be defined as a state of complete physical, mental and social well-being.
III. Among non-infectious diseases, cancer is the major cause of death.
IV. Many genera like Microsporum, Trichophyton, and Epidermophyton are reponsible for ringworms which is one of the most common infectious diseases in man.
How many of the given statements are incorrect?

Options

A. None
B. One
C. Two
D. Three

Answer

To determine how many of the given statements are incorrect, we will analyze each statement one by one.

**Step 1: Analyze Statement I**
- Statement I: "William Harvey disapproved the 'good humour' hypothesis of health."
- Explanation: The 'good humour' hypothesis suggested that health was a balance of bodily fluids (humours). William Harvey conducted experiments that led to the understanding of blood circulation and disproved this hypothesis. Therefore, this statement is **correct**.

**Step 2: Analyze Statement II**
- Statement II: "Health can be defined as a state of complete physical, mental and social well-being."
- Explanation: The World Health Organization (WHO) defines health in this manner, emphasizing that it is more than just the absence of disease. Thus, this statement is also **correct**.

**Step 3: Analyze Statement III**
- Statement III: "Among non-infectious diseases, cancer is the major cause of death."
- Explanation: Cancer is indeed one of the leading causes of death globally and is classified as a non-infectious disease. Therefore, this statement is **correct**.

**Step 4: Analyze Statement IV**
- Statement IV: "Many genera like Microsporum, Trichophyton, and Epidermophyton are responsible for ringworms which is one of the most common infectious diseases in man."
- Explanation: These genera are known to cause dermatophyte infections, including ringworm, which is indeed a common infectious disease in humans. Therefore, this statement is **correct**.

**Conclusion:**
- After analyzing all four statements, we find that all of them are correct. Therefore, the number of incorrect statements is **0**.

**Final Answer: 0**

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