Although carbon and hydrogen are better reducing agents but they are not used to reduce metallic oxides at high temperatures. Why?

Explanation

### Step-by-Step Solution:

1. **Understanding Reducing Agents**:
- Carbon and hydrogen are known to be good reducing agents. A reducing agent is a substance that donates electrons to another substance, reducing its oxidation state.

2. **High Temperature Reactions**:
- At high temperatures, many chemical reactions occur more readily, including the reduction of metallic oxides. However, the choice of reducing agent is crucial.

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