During rainy season wooden doors generally swell up due to

Options

A. Osmosis
B. Imbibition
C. Bad workmanship
D. Wood quality

Answer

### Step-by-Step Solution:

1. **Understanding the Problem**: The question asks why wooden doors swell up during the rainy season. This phenomenon is related to the interaction of wood with water.

2. **Identifying Relevant Processes**: There are several processes that can explain the swelling of wood, including osmosis, imbibition, and factors like bad workmanship or wood quality.

3. **Explaining Osmosis**: Osmosis is the movement of water across a semi-permeable membrane from a region of low solute concentration to a region of high solute concentration. However, this process is more relevant to solutions and cells rather than solid materials like wood.

4. **Explaining Imbibition**: Imbibition is a special type of diffusion where water is absorbed by solids or colloids. When dry wood absorbs water, it increases in volume. This is because the wood fibers swell as they take in moisture.

5. **Examples of Imbibition**: Common examples of imbibition include the absorption of water by dry wood and seeds. In both cases, the materials expand as they take in water.

6. **Conclusion**: During the rainy season, wooden doors absorb water from the humid environment, leading to an increase in their volume and causing them to swell. Therefore, the correct explanation for the swelling of wooden doors is imbibition.

### Final Answer:
Wooden doors swell up during the rainy season due to imbibition, where they absorb water, leading to an increase in their volume.

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