Swelling of wooden frames during rains is caused by

Options

A. Endosmosis
B. Imbibition
C. Capillarity
D. Osmosis.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why wooden frames swell during rainy conditions. This indicates a physical change in the wooden material when exposed to water.

2. **Identifying the Options**: The options provided are:
- A) Endosmosis
- B) Imbibition
- C) Capillarity
- D) Osmosis

3. **Analyzing Each Option**:
- **Endosmosis**: This refers to the movement of water into a cell when it is placed in a hypotonic solution. This process occurs at the cellular level and does not directly relate to the swelling of wooden frames.
- **Imbibition**: This is the process where solid particles absorb water without forming a solution. It is relevant to materials like wood, which can take in moisture from the environment, causing them to swell.
- **Capillarity**: This refers to the ability of a liquid to flow in narrow spaces without the assistance of external forces. While this is a property of liquids, it does not explain the swelling of wooden frames.
- **Osmosis**: This is the movement of water across a semi-permeable membrane. Like endosmosis, this process is cellular and does not apply to the swelling of wood.

4. **Conclusion**: The correct answer is **Imbibition** (Option B). This process explains how wood absorbs water from the environment, leading to its swelling during rainy conditions.

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