What is common to the following plants: Nepenthes Psilotum, Rauwolfia and Aconitum ?

Options

A. All are ornamental plants
B. All are phylogenic link species
C. All are prone to over exploitation
D. All are exclusively present in the Eastern Himalayas

Explanation

To determine what is common to the plants Nepenthes, Psilotum, Rauwolfia, and Aconitum, we can follow these steps:

### Step 1: Analyze the Plants
- **Nepenthes**: This is a genus of carnivorous plants commonly known as pitcher plants. They are known for their unique pitcher-shaped leaves that trap insects.
- **Psilotum**: This is a genus of ferns, often referred to as whisk ferns, which are primitive vascular plants.
- **Rauwolfia**: This is a genus of flowering plants known for their medicinal properties, particularly in treating hypertension.
- **Aconitum**: Also known as wolfsbane, this plant is recognized for its toxic properties but has been used in traditional medicine.

### Step 2: Evaluate the Options
- **Option A: Ornamental Plants**: While some of these plants may have ornamental value, Nepenthes is primarily known for its carnivorous nature, making this option incorrect.

- **Option B: Phylogenetically Linked Species**: The plants belong to different groups (Nepenthes and Rauwolfia are angiosperms, while Psilotum is a pteridophyte), indicating they do not share a close evolutionary relationship. Thus, this option is also incorrect.

- **Option C: Prone to Overexploitation**: All these plants have medicinal uses and are at risk due to human activities that lead to overharvesting. This option seems plausible.

- **Option D: Exclusively Present in the Eastern Himalayas**: While some of these plants may be found in the Himalayas, they are not exclusively located there. Therefore, this option is incorrect.

### Step 3: Conclusion
After evaluating the options, the common feature among Nepenthes, Psilotum, Rauwolfia, and Aconitum is that they are all **prone to overexploitation** due to their economic importance and medicinal properties.

### Final Answer
**The common feature of Nepenthes, Psilotum, Rauwolfia, and Aconitum is that they are all prone to overexploitation.**

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