Name the following
A metal oxide that can be reduced by hydrogen.

Explanation

To answer the question "Name a metal oxide that can be reduced by hydrogen," we can follow these steps:

### Step-by-Step Solution:

1. **Understand Reduction**:
- Reduction is a chemical process that involves the removal of oxygen from a substance, the addition of hydrogen, or the gain of electrons.

2. **Identify the Reactivity Series**:
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