To successfully cultivate wheat, the following conditions are essential:

1. The optimum temperature during the growing period is around 30°C: This means that wheat grows best when the temperature is around 30°C. If the temperature is too high or too low, it can affect the growth and development of the crop.

2. A frost-free period of about 100 days: Wheat is generally sensitive to frost, so it requires a frost-free period of about 100 days. This ensures that the crop can complete its growth cycle without being damaged by frost.

3. Light clay or heavy loam soil: Wheat prefers to grow in well-drained soils that are rich in organic matter. Light clay or heavy loam soils provide the ideal conditions for the crop to grow and develop properly.

From the options given, the correct answer is option 3. This means that both conditions 2 and 3 are essential for wheat cultivation, while condition 1 is not necessary.