Plants of this group are diploid and well adapted to extreme conditions. They grow bearing sporophylls in compact structures called cones. The group in reference is

Options

A. (a) Monocots
B. (b) Dicots
C. (c) Pteridophytes
D. (d) Gymnosperms

Answer

To solve the question, we need to identify the group of plants described based on the characteristics provided. Let's break down the information step by step:

### Step 1: Analyze the Characteristics
The question states that the plants in this group are:
- **Diploid**: This indicates that the dominant stage of the plant's lifecycle is the sporophyte, which is diploid.
- **Well adapted to extreme conditions**: This suggests that these plants can survive in harsh environments.
- **Grow bearing sporophylls in compact structures called cones**: This is a key feature that hints at the type of plant.

### Step 2: Identify the Plant Group
Based on the characteristics:
- The mention of **sporophylls** and **cones** is a strong indicator of gymnosperms. Gymnosperms are known for their reproductive structures called cones (or strobili) that bear the sporophylls (the leaves that bear spores).
- Gymnosperms are also predominantly diploid, as their life cycle is characterized by a dominant sporophyte stage.

### Step 3: Consider Other Plant Groups
- **Monocots and Dicots**: These are types of angiosperms (flowering plants) and do not produce cones. They have flowers instead of cones.
- **Pteridophytes**: These are non-seed plants (like ferns) and do not produce cones either.

### Step 4: Conclusion
Given the analysis, the group of plants that fits all the criteria mentioned in the question is **gymnosperms**.

### Final Answer
The group in reference is **gymnosperms**.

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