Acattle farmer is forced to use antibiotics to treat an outbreak of bacterial infections in his herd of cattle. the antibiotic is excreted by the cattle in their urine and feces and ends up in an irrigation ditch that provides water for a nearby soybean (a legume) farmer. the soybean farmer begins to notice that his soybean crop is not growing as well as usual. what might be the cause of this change in the growth of the soybeans?