3. 精读。根据关键词最后定位在第三段第三句话:“For much of the past year, President Bush campaigned to move Social Security to a Savings- account model, with retirees trading much or alll of their guaranteed payments for payments depending on investment returns。” 从词句中的“把有保障的收入(guaranteed payments)变成必须依靠投资收益的收入 (payments depending on investment returns)”可知其养老金的风险越来越大,因此B项 less secured payments符合题意。