Some bio-indicator plant have evolved metal tolerance, and can indicate the occurrence of specific indicator of lead is

Options

A. Agrostis tenuis
B. Astragalus
C. Haplopappus
D. Imaptients balsamina

Answer

**Step-by-Step Solution:**

1. **Understanding Bioindicators**: Begin by defining what bioindicators are. Bioindicators are organisms or substances that provide information about the health of an ecosystem or the presence of specific environmental conditions, particularly pollutants or metals.

2. **Identifying the Metal in Question**: The question specifies lead as the metal of interest. The chemical symbol for lead is Pb.

3. **Analyzing the Options**: We have four plant options to evaluate for their ability to indicate the presence of lead:
- **Agrostis tenuis**
- **Agrostis** (likely a typo, should be a different species)
- **Haplopappus**
- **Impatiens balsamina**

4. **Evaluating Each Plant**:
- **Agrostis tenuis**: This plant is known to exhibit lead tolerance and can change color in the presence of lead, indicating its presence effectively.
- **Agrostis**: This option seems to be incomplete or incorrect, as it does not specify a species known for lead indication.
- **Haplopappus**: This plant is known to indicate selenium, not lead.
- **Impatiens balsamina**: This plant is known to indicate arsenic, not lead.

5. **Conclusion**: Based on the evaluations, the only plant that indicates the presence of lead is **Agrostis tenuis**. Therefore, the correct answer is option 1: **Agrostis tenuis**.

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