A: Louis Pasteur discovered that fermentation is brought about by micro-organisms
R:Parasitic bacteria bring about fermentation.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the assertion and reason question, we will analyze both the assertion (A) and the reason (R) statements step by step.

### Step 1: Analyze the Assertion (A)
The assertion states: "Louis Pasteur discovered that fermentation is brought about by micro-organisms."

- **Explanation**: This statement is true. Louis Pasteur is well-known for his work on fermentation, where he demonstrated that it is caused by the activity of microorganisms, particularly yeasts and bacteria.

### Step 2: Analyze the Reason (R)
The reason states: "Parasitic bacteria bring about fermentation."

- **Explanation**: This statement is false. Fermentation is primarily carried out by certain types of bacteria and yeasts, specifically heterotrophic bacteria, which are often saprophytic (decomposing organic matter) rather than parasitic. Parasitic bacteria typically feed on living hosts, which is not the case in fermentation processes.

### Step 3: Conclusion
Since the assertion (A) is true and the reason (R) is false, we can conclude that the correct relationship between A and R is that A is true, but R is false.

### Final Answer
The correct answer is that the assertion is true and the reason is false.

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