Explanation:

- In the northern and north-western part of India, the primary food crop is wheat.

- These regions have a climate favorable for wheat cultivation.

- Wheat is widely grown due to its adaptability to cooler temperatures and less rainfall, which these areas experience.

- Rice is more dominant in areas with abundant water supply and higher temperatures, such as eastern and southern India.

- It requires a lot of water for cultivation, making it less suitable for the northern parts.

- Maize can be found in various parts of India but is not the main staple food crop in the northern regions.

- Millets are drought-resistant grains.

- They are often found in drier parts of India, but not the main crop in the north.

Correct Answer: 1. Wheat