Maize, rice and wheat are rich in ............ food.

Explanation

**Step-by-Step Solution:**

1. **Identify the Foods:** The question mentions three specific foods: maize, rice, and wheat.

2. **Understand Their Nutritional Content:** These foods are staple crops that are commonly consumed around the world. They are known for their high energy content.

3. **Determine the Main Nutrient:** The primary nutrient that these foods provide is carbohydrates. More specifically, they are rich in starch, which is a type of carbohydrate.

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