The sub- division under plant kingdom which includes all ferns is___________ .

Explanation

**Step-by-Step Solution:**

1. **Identify the Plant Kingdom**: The question asks about a specific subdivision within the plant kingdom that encompasses all ferns.

2. **Recall the Subdivisions of the Plant Kingdom**: The plant kingdom is divided into several subdivisions, including Bryophyta (mosses), Pteridophyta (ferns), Gymnosperms (conifers), and Angiosperms (flowering plants).

3. **Focus on Ferns**: Since the question specifically mentions ferns, we need to identify which subdivision includes ferns.

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