Only poisonous lizard of the world is

Options

A. Ophiosaurus
B. Varanus
C. Heloderma
D. Draco

Answer

**Step-by-Step Solution:**

1. **Understand the Classification of Lizards**: Lizards belong to the class Reptilia, which indicates that they are reptiles. They have certain characteristics such as rough skin, separate sexes, and they reproduce sexually.

2. **Identify the Characteristics of Reptiles**: Reptiles, including lizards, are oviparous (they lay eggs), have direct development, and are poikilothermic (their body temperature varies with the environment).

3. **Evaluate the Options**: The question provides four options for the only poisonous lizard:
- **Ophiosaurus**: Known as the glass snake, it is a limbless lizard but is not poisonous.
- **Veranus**: Commonly referred to as monitor lizards, they are not known to be poisonous.
- **Heloderma**: This is the only known poisonous lizard, possessing venomous glands.
- **Draco**: Known as the flying lizard, it is not poisonous.

4. **Identify the Poisonous Lizard**: Among the options, Heloderma stands out as the only poisonous lizard. Its venom glands are modified forms of sublingual glands.

5. **Conclude the Answer**: Therefore, the correct answer to the question is Heloderma.

**Final Answer**: The only poisonous lizard in the world is **Heloderma**.

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