Answer:
The answer includes all of the options.
Step-by-step explanation:
Some of the major changes that happened in agriculture during the 1920s include the use of electrical tools and vehicles and chemical fertilizers. These changes along with their low availability to the average farmers made it harder for them to compete with agricultural corporations who could use these advanced methods easily. Hybrid seeds were also used by corporations to get increase the yield of the fields. The answer includes all of the options.
I hope this answer helps.