Choose the incorrect statements

Options

A. parasite might render the host more vulnerable to predation by making it physically weak
B. majority of the parasites harm the host and reduce the population density
C. ideal parasite should be able to thrve with in host without harming it
D. malarial parasite does not need a vector (mosquito) to spread to the host

Answer

To solve the question of identifying the incorrect statements from the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Parasitism**:
- Parasitism is a type of interaction where one organism (the parasite) benefits at the expense of another organism (the host). The host is harmed in this interaction.

2. **Evaluate the First Statement**:
- The first statement claims that "Parasite might render the host more vulnerable to predation by making it physically weak."
- This statement is correct because parasites can weaken their hosts, making them more susceptible to predators.

3. **Evaluate the Second Statement**:
- The second statement mentions, "Some parasites feed on the surface of the host and this type of host is known as ectoparasites."
- This statement is also correct as ectoparasites live on the surface of the host.

4. **Evaluate the Third Statement**:
- The third statement states, "Ideal parasites should be able to thrive within the host without harming it."
- This statement is correct in the context of an ideal scenario for a parasite, as it would benefit from the host without killing it.

5. **Evaluate the Fourth Statement**:
- The fourth statement claims, "Malarial parasite does not need a vector mosquito to spread to the host."
- This statement is incorrect because the malarial parasite (Plasmodium) requires a mosquito as a vector to complete its life cycle and infect humans.

6. **Conclusion**:
- The incorrect statement among the options provided is the fourth one.

### Final Answer:
The incorrect statement is: **"Malarial parasite does not need a vector mosquito to spread to the host."**

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