Single land mass present before `250` million years ago has been named as

Options

A. Panthalassa
B. Laurasia
C. Gondwanaland
D. Pangaea.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the single landmass that existed before 250 million years ago.

2. **Identifying the Relevant Theory**: The theory that explains the existence of this single landmass was proposed by Alfred Wegener. He introduced the concept of continental drift.

3. **Explaining the Concept of Pangaea**: According to Wegener's theory, around 335 million years ago, all the continents were joined together to form a single supercontinent known as Pangaea.

4. **Timeline of Continental Separation**: Wegener suggested that Pangaea began to break apart approximately 175 million years ago, leading to the formation of the continents as we know them today.

5. **Conclusion**: Therefore, the name of the single landmass that existed before 250 million years ago is **Pangaea**.

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