Most slaves were field-workers, easliy replaced, and therefore

a) hired out to city folk when crops were harvested
b) treatment varied with the personality of the land owner
c) many were owned to harvest crops faster
d) relationships with england continued with sale of cotton

B) treatment varied with the personality of the land owner.

Because most slaves were field-workers, lacked formal education, and possessed little technical skills, replacements were easily found. This contributed to the ill-treatment of some, as land owners had complete power over them. Other factors that contributed to the abuse was the lack of protections from the government and the abundance of slave labour.

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missouri compromise of 1820 which prohibited slavery