Which of the following pairs of plants represents conifers ?

Options

A. Cycas and Ginkgo
B. Pinus and Cedrus
C. Pinus and Eucalyptus
D. Cycas and wolffia

Answer

To determine which pair of plants represents conifers, we need to understand what conifers are and identify them among the given options.

### Step-by-Step Solution:

1. **Understanding Conifers**:
- Conifers are a group of plants that belong to the class Gymnosperms. The term "Gymnosperm" means "naked seeds," which indicates that their seeds are not enclosed within an ovary wall.

2. **Identifying Characteristics of Conifers**:
- Conifers typically have needle-like leaves, which help reduce water loss.
- They often have thick cuticles and sunken stomata to further minimize water loss.

3. **Analyzing the Options**:
- **Option 1: Cycas and Ginkgo**:
- Cycas is a gymnosperm, but Ginkgo is not a conifer; it belongs to a different group of gymnosperms.
- **Option 2: Pinus and Cedrus**:
- Both Pinus (pine trees) and Cedrus (cedar trees) are well-known examples of conifers.
- **Option 3: Pinus and Eucalyptus**:
- While Pinus is a conifer, Eucalyptus is a flowering plant (angiosperm), not a conifer.
- **Option 4: Cycas and Wolffia**:
- Cycas is a gymnosperm, but Wolffia is an aquatic plant and not related to conifers.

4. **Conclusion**:
- The only option that contains two plants that are both conifers is **Option 2: Pinus and Cedrus**.

### Final Answer:
The pair of plants that represents conifers is **Pinus and Cedrus**.

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