Oxygen was discovered by

Options

A. Priestley
B. Boyle
C. Scheele
D. Cavendish

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who discovered oxygen.

2. **Recall Historical Figures**: When thinking about the discovery of oxygen, it is important to recall key scientists involved in its identification and naming.

3. **Recognize Key Contributions**:
- Carl Wilhelm Scheele is credited with the discovery of oxygen in 1771.
- However, it was Antoine Lavoisier who later named the element "oxygen" in 1777.

4. **Review the Options Provided**: The options given in the question are:
- 1. Priestly
- 2. Boyle
- 3. Scheele
- 4. Cavendish

5. **Select the Correct Answer**: Based on historical records, Carl Wilhelm Scheele is the correct answer as he discovered oxygen first. Therefore, the answer to the question "Oxygen was discovered by" is option 3: Scheele.

**Final Answer**: Oxygen was discovered by Carl Wilhelm Scheele.

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