A drinking straw works on the pressure exerted by the liquid filled in a soft drink bottle in which it is placed.

Explanation

### Step-by-Step Solution:

1. **Understanding the Drinking Straw Mechanism**:
- A drinking straw is a simple device used to draw liquids into the mouth. It operates based on the principles of pressure differences.

2. **Identifying the Pressure in the Bottle**:
- The liquid in the soft drink bottle exerts pressure due to its weight and the atmospheric pressure acting on the liquid surface. However, this pressure alone does not cause the liquid to rise in the straw.

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