..................method is used to separate wheat grains from its husk.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Mixture**: We start with a mixture of wheat grains and husk. The wheat grains are heavier, while the husk is lighter.

2. **Identifying the Separation Method**: The question asks for the method used to separate these two components. The appropriate method for this separation is called "winnowing."

3. **Explaining Winnowing**: Winnowing is a process that utilizes wind or air to separate lighter and heavier components of a mixture. In this case, the wind helps to blow away the lighter husk while the heavier wheat grains fall down.

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