Analysis of the Word Relationship

The question asks to identify which of the given words is a "necessary part" of the word "harvest". This means the concept of harvesting cannot exist without the concept of the chosen word.

The definition of harvest is the process or period of gathering in crops.

Evaluating the Options:

• A. autumn: While many harvests occur in autumn, harvests also happen in spring and summer. Therefore, autumn is not a necessary part.
• B. crop: The very definition of harvesting involves gathering crops. Without a crop, there is nothing to harvest. Therefore, a crop is a necessary part.
• C. stockpile: A stockpile may be created after a harvest, but it is not essential. The harvested crop could be consumed or sold immediately. Therefore, a stockpile is not a necessary part.
• D. tractor: A tractor is a modern tool used for harvesting, but harvesting can also be done by hand or with other tools. Therefore, a tractor is not a necessary part.

Conclusion

The only word that is essential to the definition of "harvest" is crop.