Which of the following is called as "Adder's tongue Fern" :-

Options

A. Cyathea
B. Marsilea
C. Ophioglossum
D. Adiantum

Answer

**Step-by-Step Solution:**

1. **Identify the Common Name:** The question asks for the organism commonly known as "Adder's Tongue Fern."

2. **Research the Organism:** The scientific name associated with the common name "Adder's Tongue Fern" is Ophioglossum.

3. **Understand the Habitat:** Ophioglossum is known to grow in various habitats such as old grasslands, hillsides, woodlands, and sand dunes.

4. **Growth Characteristics:** This fern typically appears during the months of June and August, and for the rest of the year, it remains underground in the form of a rhizome.

5. **Reason for the Name:** The name "Adder's Tongue" is derived from the appearance of its spore-bearing stalk, which resembles a snake's tongue.

6. **Conclusion:** Based on the information gathered, the answer to the question is Ophioglossum, which is the third option.

**Final Answer:** Ophioglossum is called Adder's Tongue Fern.

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