Assertion : Fish and other varieties of aquatic animals are used as food.
Reason : Fish and other varieties of sea food constitute good source of nutrition.

Options

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

Explanation

To solve the question regarding the assertion and reason, we can follow these steps:

### Step 1: Understand the Assertion
The assertion states that "Fish and other varieties of aquatic animals are used as food." This means that fish and seafood are commonly consumed by people.

### Step 2: Understand the Reason
The reason provided is that "Fish and other varieties of seafood constitute a good source of nutrition." This indicates that fish and seafood provide essential nutrients that are beneficial for health.

### Step 3: Evaluate the Assertion
The assertion is true because fish and aquatic animals are indeed widely consumed across various cultures and cuisines. They are a staple food in many regions.

### Step 4: Evaluate the Reason
The reason is also true. Fish is known to be rich in proteins, vitamins, and minerals such as calcium and phosphorus, which are crucial for the growth and development of the body.

### Step 5: Determine the Relationship
Since both the assertion and the reason are true, we need to check if the reason correctly explains the assertion. The reason does explain why fish and aquatic animals are used as food, as they provide essential nutrients.

### Step 6: Conclusion
Both the assertion and reason are true, and the reason is the correct explanation of the assertion. Therefore, the answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
The correct option is: "Assertion and reason are true but reason is the correct explanation of assertion."

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