In some plants, the leaves are shortlived and small. The petioles of such plants expand and become green. One such plant is:

Options

A. Cactus
B. Venus fly-trap
C. Australian acacia
D. Peas

Answer

To solve the question regarding which plant has short-lived and small leaves with expanded green petioles, we can follow these steps:

### Step 1: Understand the Characteristics of the Plants
We need to analyze the characteristics of the plants mentioned in the options. This includes understanding how their leaves and petioles are modified.

### Step 2: Analyze Each Option
1. **Cactus**: Cacti have modified leaves in the form of spines, which help to reduce transpiration. The leaves are not short-lived; instead, they are absent or highly modified.

2. **Venus Flytrap**: This plant has modified leaves that are specialized for trapping insects. These leaves are not small and short-lived in the context of petiole modification.

3. **Australian Acacia**: This plant has very small and short-lived leaves. The petioles of Acacia are modified to perform the function of leaves, which allows them to reduce transpiration loss effectively.

4. **Peas**: Peas have tendrils that are modified leaves, which help the plant climb. The leaves are not particularly short-lived or small in the context of petiole modification.

### Step 3: Identify the Correct Answer
From the analysis, the Australian Acacia is the only plant that fits the description of having short-lived and small leaves with expanded green petioles. The petioles take over the function of leaves, which is a significant adaptation.

### Final Answer
The correct answer is **Australian Acacia**.

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