A : Nitrate and phosphate discharge in a water body causes eutrophication.
R : This increases the inorganic content in water body and hence growth of algal blooms

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are ture but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**: The assertion states that "Nitrate and phosphate discharge in a water body causes eutrophication."
- Eutrophication is a process that occurs when water bodies receive excess nutrients, primarily nitrogen and phosphorus, which leads to increased plant growth and decay.

2. **Understanding the Reason (R)**: The reason states that "This increases the inorganic content in the water body and hence growth of algal blooms."
- When nitrates and phosphates are discharged into a water body, they increase the nutrient levels, which can lead to the rapid growth of algae, known as algal blooms.

3. **Connecting A and R**: The assertion and reason are connected. The increase in nitrates and phosphates (assertion) leads to higher inorganic content in the water, which promotes algal growth (reason).

4. **Evaluating the Truth of A and R**: Both statements are true.
- The assertion is correct because nutrient discharge does indeed cause eutrophication.
- The reason is also correct as the increase in inorganic content directly contributes to the growth of algal blooms.

5. **Conclusion**: Since both the assertion and reason are true, and the reason correctly explains the assertion, the correct answer is that both A and R are true, and R is the correct explanation of A.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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