Two sets A and B, of three bulbs each, are glowing in two separate rooms. When one of the bulbs in set A is fused, the other two bulbs also cease to glow. But in set B, when one bulb fuses, the other two bulbs continue to glow. Explain why this phenomenon occurs.

Explanation

### Step-by-Step Solution:

1. **Understanding the Setup**: We have two sets of bulbs, Set A and Set B, each containing three bulbs. They are located in separate rooms.

2. **Behavior of Bulbs in Set A**: When one bulb in Set A is fused (broken), all three bulbs cease to glow. This indicates that the bulbs are connected in a way that if one bulb fails, it affects the others.

3. **Behavior of Bulbs in Set B**: In contrast, when one bulb in Set B is fused, the other two bulbs continue to glow. This suggests that the bulbs in Set B are connected differently than those in Set A.

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