What happens when
Tea leaves, cotton swabs and old soft toys are thrown into the drain

Explanation

**Step-by-Step Solution:**

1. **Identify the Materials**: The materials in question are tea leaves, cotton swabs, and old soft toys. Each of these items belongs to different waste categories: organic waste (tea leaves), non-biodegradable waste (cotton swabs), and potentially non-biodegradable waste (old soft toys).

2. **Impact on Drainage System**: When these items are thrown into the drain, they do not break down easily. The tea leaves can clump together, while cotton swabs and soft toys are too large to pass through the drainage pipes.

3. **Blockage Formation**: As these materials accumulate in the drain, they create a blockage. This blockage prevents water from flowing freely through the pipes, leading to a backup in the drainage system.

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