Fill in each blank with the suitable words given in the box.
(cutting ,asexual , sexual, grafting , tuber, bulb , spore)
A piece of stem or leaf may be a ______

Explanation

To fill in the blank in the sentence "A piece of stem or leaf may be a ______," we need to analyze the options provided and determine which one fits best.

1. **Understanding the Options**: The words provided are: cutting, asexual, sexual, grafting, tuber, bulb, and spore.

2. **Identifying the Context**: The sentence refers to a piece of stem or leaf. In biological terms, a piece of stem or leaf is often used in plant propagation methods.

3. **Evaluating Each Option**:
- **Cutting**: This refers to a method of asexual reproduction where a piece of a plant (like a stem or leaf) is cut and planted to grow a new plant.
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