The stem of one of the following plants can do photosynthesis. This plant is :

Options

A. mushroom
B. croton
C. cuscuta
D. cactus

Answer

**Step-by-Step Solution:**

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants use sunlight to synthesize foods with the help of chlorophyll, primarily found in leaves.

2. **Identifying the Plants**: The plants mentioned in the question are mushroom, croton, cascuita, and cactus. We need to determine which of these can perform photosynthesis through its stem.

3. **Analyzing Each Plant**:
- **Mushroom**: This is a type of fungi and does not perform photosynthesis. It is a saprotroph, meaning it derives nutrients from dead and decaying organic matter.
- **Croton**: This is a flowering plant that primarily conducts photosynthesis in its leaves. The stem does not have chlorophyll, so it cannot perform photosynthesis.
- **Cascuita**: This is a parasitic plant that does not perform photosynthesis, as it relies on other plants for nutrients.
- **Cactus**: The cactus has a green, fleshy stem that contains chlorophyll, allowing it to perform photosynthesis. In cacti, the leaves are reduced to spines, and the stem takes over the role of photosynthesis.

4. **Conclusion**: Among the options provided, the cactus is the only plant whose stem can perform photosynthesis.

**Final Answer**: The plant whose stem can do photosynthesis is the **cactus**.

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