A reservior of infection is the one is which

Options

A. Large scale infection occurs
B. The pathogen resides without producing disease
C. The pathogen passes its sexual phase
D. The pathogen passes its asexual phase

Answer

To solve the question "A reservoir of infection is the one in which," we need to analyze the options provided and identify which one correctly describes a reservoir of infection.

### Step-by-Step Solution:

1. **Understand the Concept of Reservoir of Infection**:
A reservoir of infection refers to a natural habitat where a pathogen lives, grows, and multiplies. It can be a person, animal, or environment that harbors the pathogen.

2. **Evaluate Each Option**:
- **Option A**: "A large-scale infection occurs."
- This option describes an outbreak rather than a reservoir. A reservoir does not necessarily imply a large-scale infection.

- **Option B**: "The pathogen resides without producing diseases."
- This option accurately describes a reservoir. In many cases, the pathogen can exist in a host without causing disease, allowing it to be transmitted to others.

- **Option C**: "The pathogen passes its sexual phase."
- This option is not relevant to the definition of a reservoir. While some pathogens may have sexual phases, it does not define a reservoir.

- **Option D**: "The pathogen passes its asexual phase."
- Similar to option C, this does not define a reservoir. Asexual reproduction can occur in various environments but does not specifically relate to the concept of a reservoir.

3. **Select the Correct Answer**:
Based on the analysis, the correct answer is **Option B**: "The pathogen resides without producing diseases."

### Final Answer:
The correct answer is **Option B**: The pathogen resides without producing diseases.

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