(A]: The relationship between sucker fish and shark is considered to be an example of parasitism.
[R]: Sucker fish gets food and shelter from shark and also alters the population growth of the shark

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To analyze the relationship between sucker fish and sharks, we can break down the question into two parts: the assertion (A) and the reason (R).

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the relationship between sucker fish and sharks is an example of parasitism.
- Parasitism is defined as a relationship where one organism (the parasite) benefits at the expense of another organism (the host).

2. **Analyzing the Relationship**:
- Sucker fish attach themselves to sharks and feed on leftover food particles when sharks hunt.
- In this relationship, the sucker fish benefits by obtaining food and shelter from the shark.

3. **Understanding the Reason (R)**:
- The reason states that sucker fish get food and shelter from sharks and also alter the population growth of the shark.
- While it is true that sucker fish get food and shelter, the claim that they alter the population growth of sharks is not supported by evidence.

4. **Identifying the Type of Interaction**:
- The relationship is more accurately described as commensalism rather than parasitism. In commensalism, one organism benefits while the other is neither helped nor harmed.
- In this case, the sucker fish benefits, while the shark does not receive any significant benefit or harm from the presence of the sucker fish.

5. **Conclusion**:
- Therefore, the assertion (A) is true in stating that sucker fish and sharks have a relationship, but it is not parasitism. The reason (R) is false because it incorrectly suggests that sucker fish alter the population growth of sharks.

### Final Answer:
- Assertion (A) is true, but Reason (R) is false.