Assertion: `C_(3)` plants respond to increased `CO_(2)` concentration by increaing rate of photosyntheis. ltbr. Reason: The higher productivity of some greenhouse crops such as tomatoes and bell pepper is due to increased `CO_(2)` concentration

Explanation

To analyze the assertion and reason provided in the question, we can break down the solution step by step:

### Step 1: Understand the Assertion
The assertion states that C3 plants respond to increased CO2 concentration by increasing the rate of photosynthesis.

- **Explanation**: C3 plants, such as mustard, barley, and spinach, utilize carbon dioxide in the process of photosynthesis. When CO2 levels rise, the rate of photosynthesis in these plants typically increases, provided that other factors such as light intensity are also adequate.

### Step 2: Understand the Reason
The reason given is that the higher productivity of some greenhouse crops, such as tomatoes and bell peppers, is due to increased CO2 concentration.

- **Explanation**: In controlled greenhouse environments, CO2 levels can be elevated to enhance photosynthesis, leading to increased growth and yield of crops like tomatoes and bell peppers. This is a common agricultural practice to boost productivity.

### Step 3: Evaluate the Relationship Between Assertion and Reason
Now, we need to determine if the reason supports the assertion.

- **Analysis**: Both the assertion and reason are true statements. However, the reason does not directly explain why C3 plants respond to increased CO2 concentration. The assertion is about the general behavior of C3 plants, while the reason specifically addresses greenhouse crops, which may include both C3 and C4 plants.

### Conclusion
- **Final Statement**: Both the assertion and reason are true, but the reason does not adequately support the assertion. Therefore, the correct conclusion is that while both statements are true, they are not directly related to each other.

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