Select one: a. Copper contamination in the soil created copper-tolerant plants b. Prior to mining, the population contained both copper-tolerant and copper-intolerant plants c. Once mining began, mutation created the copper-tolerant allele that the plants needed to survive d. High mutation rates resulted in the fixation of the copper-tolerance allele

a. Copper contamination in the soil created copper-tolerant plants.

Explanation:

Those plants that are cultivated on the soil having high concentration of copper in the soil creates tolerance to copper and becomes copper tolerant crops. Copper is a metal which is required for the process of photosynthesis and component of many enzymes but excess amount of copper cause damage to the plants especially root tips. But there are several plants which are tolerance to high amount of copper in the soil such as monkey flowers.

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consuming the right balance of protein, carbohydrates and fat can you maintain a healthy weight and optimize your energy levels. protein and carbohydrates both contain 4 calories per gram, while fat provides 9 calories per gram.