`CH_4 + O_ 2 to CO_2 + H_2O` is a chemical equation
The reactants are

Options

A. `CH_4,CO_2`
B. `H_2O,O_2`
C. `CO_2,H_2O`
D. `CH_4,O_2`

Explanation

To determine the reactants in the chemical equation `CH_4 + O_2 → CO_2 + H_2O`, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of the Equation**:
The equation consists of two sides: the left side (reactants) and the right side (products).

2. **Locate the Reactants**:
In the equation `CH_4 + O_2 → CO_2 + H_2O`, the substances on the left side of the arrow are the reactants.

3. **List the Reactants**:
From the equation, we can see that the reactants are:
- `CH_4` (Methane)
- `O_2` (Oxygen)

4. **Confirm the Products**:
The substances on the right side of the arrow are the products, which are:
- `CO_2` (Carbon Dioxide)
- `H_2O` (Water)

5. **Conclusion**:
Therefore, the reactants in the given chemical equation are `CH_4` and `O_2`.

### Final Answer:
The reactants are `CH_4` and `O_2`.

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