Assertion(A): Fihses are called ammoniatelic animals
Reasoning(R): They contains nephrons which filter the blood and form the urine and large amount of ammonia is found in fish excreta.
Choose the correct answer

Options

A. A is correct and R is the correct explanation of A.
B. A is correct and R is not the correct explanation of A.
C. A is correct and R is wrong.
D. A is wrong and R is correct.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that "Fishes are called ammoniatelic animals." This means that fishes primarily excrete ammonia as their nitrogenous waste.

2. **Understanding the Reasoning**: The reasoning provided states that "They contain nephrons which filter the blood and form the urine, and a large amount of ammonia is found in fish excreta." This indicates that fishes have a specific mechanism (nephrons) for filtering blood and producing urine, which contains a high concentration of ammonia.

3. **Analyzing the Assertion**: It is true that most fishes (approximately 90%) are classified as ammoniatelic because they excrete ammonia directly into the water. This is an adaptation to their aquatic environment, where ammonia can be diluted easily.

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