最后一句话The plan has good chances of success,since sweet potato is a staple of the region’s diet and agriculture, and the varieties currently grown contain little beta-carotene. 中 the plan has good chances of success.是结论。 答题点 是找其他原因,也能表达对结论支持的观点。A the condition can flourish the growing of the S,thus support the conclusion. C有表达出对结论的任何作用吗?再回读一下 肯定没有啊 不要被误导啊