Gymnosperm plants lack :-

Options

A. Vessels
B. Fruits
C. Companion cells
D. All the above

Answer

### Step-by-Step Solution:

1. **Understanding Gymnosperms**:
- Gymnosperms are a group of seed-producing plants that include conifers and cycads. They are characterized by having seeds that are not enclosed in an ovary (fruit), which is why they are referred to as "naked seeds."

2. **Identifying Structures Lacking in Gymnosperms**:
- **Fruits**: Gymnosperms do not produce fruits because their seeds are not enclosed within an ovary. This is a defining feature of gymnosperms.
- **Vessels in Xylem**: In gymnosperms, the xylem primarily consists of tracheids for water conduction, and they lack vessel elements, which are present in angiosperms (flowering plants).
- **Companion Cells in Phloem**: Gymnosperms do not have companion cells in their phloem. Instead, they have sieve cells that serve a similar function but are structurally different.

3. **Evaluating the Options**:
- The question provides four options: vessels, fruits, companion cells, or all of the above.
- Based on the characteristics of gymnosperms discussed:
- **Vessels**: Absent in gymnosperms.
- **Fruits**: Absent in gymnosperms.
- **Companion Cells**: Absent in gymnosperms.
- Since all three structures are absent in gymnosperms, the correct answer is "all of the above."

4. **Conclusion**:
- Therefore, the correct answer to the question "Gymnosperm plants lack:" is **D) all of the above**.